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Crystal structures of (RS)-N-[(1R,2S)-2-benz­yl­oxy-1-(2,6-di­methyl­phen­yl)prop­yl]-2-methyl­propane-2-sulfinamide and (RS)-N-[(1S,2R)-2-benz­yl­oxy-1-(2,4,6-tri­methyl­phen­yl)prop­yl]-2-methyl­propane-2-sulfinamide: two related protected 1,2-amino alcohols

aDepartment of Chemistry, 120 Trustee Road, 412 Hutchison Hall, University of Rochester, Rochester, NY 14627, USA
*Correspondence e-mail: weix@chem.rochester.edu

Edited by H. Stoeckli-Evans, University of Neuchâtel, Switzerland (Received 26 September 2014; accepted 14 October 2014; online 24 October 2014)

The title compounds, C22H31NO2S, (1), and C23H33NO2S, (2), are related protected 1,2-amino alcohols. They differ in the substituents on the benzene ring, viz. 2,6-di­methyl­phenyl in (1) and 2,4,6-tri­methyl­phenyl in (2). The plane of the phenyl ring is inclined to that of the benzene ring by 28.52 (7)° in (1) and by 44.65 (19)° in (2). In the crystal of (1), N—H⋯O=S and C—H⋯O=S hydrogen bonds link mol­ecules, forming chains along [100], while in (2), similar hydrogen bonds link mol­ecules into chains along [010]. The absolute structures of both compounds were determined by resonance scattering.

1. Chemical context

1,2-Amino alcohols are found in a variety of pharmaceutically active compounds (Lee & Kang, 2004[Lee, H.-S. & Kang, S. H. (2004). Synlett, pp. 1673-1685.]) and have been used extensively as components of chiral ligands and auxiliaries in asymmetric synthesis (Ager et al., 1996[Ager, D. J., Prakash, I. & Schaad, D. R. (1996). Chem. Rev. 96, 835-876.]; Pu & Yu, 2001[Pu, L. & Yu, H.-B. (2001). Chem. Rev. 101, 757-824.]). In order to develop new chiral ligands and as part of an advanced undergraduate laboratory course, we sought to make a series of 2-aryl-1-methyl-1,2-amino alcohols. The most straightforward synthesis of these compounds was reported by Ellman (Tang et al., 2001[Tang, T. P., Volkman, S. K. & Ellman, J. A. (2001). J. Org. Chem. 66, 8772-8778.]; Evans & Ellman, 2003[Evans, J. W. & Ellman, J. A. (2003). J. Org. Chem. 68, 9948-9957.]). The method relies upon the chiral ammonia equivalent, 2-methyl-2-propane­sulfinamide (tert-butane­sulfinamide), which is readily available from a variety of commercial sources or easily synthesized on scale (Weix et al., 2005[Weix, D. J., Ellman, J. A., Wang, X. & Curran, D. P. (2005). Org. Synth. 82, 157-165.]). In the original Ellman report, the absolute configuration of the products was determined by deprotection of the amine and alcohol, cyclization to form the corresponding oxazolidinone, and correlation of the 1H NMR spectra with the literature (Zietlow & Steckhan, 1994[Zietlow, A. & Steckhan, E. (1994). J. Org. Chem. 59, 5658-5661.]).

[Scheme 1]

We report herein on the syntheses and structures of two different but related protected 1,2-amino alcohols, (1) and (2), from the addition of an aryl­magnesium bromide to an N-tert-butane­sulfinyl imine (Evans & Ellman, 2003[Evans, J. W. & Ellman, J. A. (2003). J. Org. Chem. 68, 9948-9957.]). The reaction of imine (3a) with xylylmagnesium bromide, (4a), (see Fig. 1[link]) resulted in a mixture of amino alcohol products from which the major product of the reaction, (1), was isolated in 27% yield after chromatographic separation of the diastereomers. The stereochemistry of this major product was confirmed by X-ray diffraction and the result is consistent with the sense of induction reported by Evans & Ellman (2003[Evans, J. W. & Ellman, J. A. (2003). J. Org. Chem. 68, 9948-9957.]).

[Figure 1]
Figure 1
(Top) Reaction scheme depicting the synthesis of (1) and (5) from (3a), for which (1) is the major product of the reaction. (Bottom) Reaction scheme depicting the synthesis of (6) and (7) from (3a), and (8) and (2) from (3b), for which (6) is the major product of the reaction from (3a), and (8) is the major product from (3b).

The analogous reaction with mesitylmagnesium bromide, (4b), also resulted in a mixture of products, from which the major product, (6), was isolated in 43% yield. A mixture of other diastereomers was also isolated, from which a crystal suitable for X-ray diffraction was grown. Unexpectedly, X-ray analysis showed this crystal to be (2), a product that could only have derived from a diastereomerically different isomer of (3a). Upon further investigation, we discovered that the starting material, which we had assumed was pure (3a), contained the minor diastereomer, (3b), in about 8% (determined by 1H NMR; Fontenelle et al., 2014[Fontenelle, C. Q., Conroy, M., Light, M., Poisson, T., Pannecoucke, X. & Linclau, B. (2014). J. Org. Chem. 79, 4186-4195.]), which had formed due to racemization in the synthesis of (3a). Based on the work of Evans & Ellman (2003[Evans, J. W. & Ellman, J. A. (2003). J. Org. Chem. 68, 9948-9957.]), it was deduced that (2) is the minor product expected from the reaction of (3b) with an aryl­magnesium bromide. Although no further separations were performed on this mixture that contained (2), it follows that the other diastereomers present were (7), the minor product from the reaction with (3a), and (8), the major product from the reaction with the slight impurity of (3b).

2. Structural commentary

The mol­ecular structures of compounds (1) and (2) are illus­trated in Figs. 2[link] and 3[link], respectively. The essential difference in the conformation of the two compounds is that the phenyl ring (C5–C10) is inclined to the benzene ring (C11–C16) by 28.52 (7)° in (1) and by 44.65 (19)° in (2).

[Figure 2]
Figure 2
The mol­ecular structure of compound (1), with atom labelling. Displacement ellipsoids are drawn at the 50% probability level.
[Figure 3]
Figure 3
The mol­ecular structure of compound (2), with atom labelling. Displacement ellipsoids are drawn at the 50% probability level.

3. Supra­molecular features

In the crystals of both (1) and (2), chains are formed via inter­molecular hydrogen bonding (Tables 1[link] and 2[link]). In (1), mol­ecules are linked along the [100] direction by a combination of classical (N—H⋯O=S) and non-classical (C—H⋯O=S) hydrogen bonds (Table 1[link] and Fig. 4[link]). In (2), mol­ecules are linked along the [010] direction also by classical (N—H⋯O=S) and non-classical (C—H⋯O=S) hydrogen bonds (Table 2[link] and Fig. 5[link]).

Table 1
Hydrogen-bond geometry (Å, °) for (1)[link]

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1⋯O2i 0.84 (2) 2.23 (2) 3.0039 (15) 152.8 (7)
C18—H18A⋯O2i 0.98 2.52 3.4077 (17) 150
C23—H23B⋯O2i 0.98 2.59 3.5534 (17) 167
Symmetry code: (i) [x+{\script{1\over 2}}, -y+{\script{1\over 2}}, -z].

Table 2
Hydrogen-bond geometry (Å, °) for (2)[link]

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1⋯O2i 0.83 (4) 2.08 (4) 2.890 (4) 169 (4)
C7—H7A⋯O1ii 0.95 2.59 3.501 (6) 160
Symmetry codes: (i) [-x, y+{\script{1\over 2}}, -z+1]; (ii) x, y+1, z.
[Figure 4]
Figure 4
A partial view of the crystal packing of compound (1), illustrating the formation of the hydrogen-bonded chains along [100] (hydrogen bonds are shown as dashed lines; see Table 1[link] for details). Displacement ellipsoids are drawn at the 50% probability level.
[Figure 5]
Figure 5
A partial view of the crystal packing of compound (2), illustrating the formation of the hydrogen-bonded chains along [010] (hydrogen bonds are shown as dashed lines; see Table 2[link] for details). Displacement ellipsoids are drawn at the 50% probability level.

4. Database survey

Although there are 78 structures of N-sulfinyl-protected 1,2-amino alcohols in the Cambridge Structural Database (CSD, Version 5.35, last update May 2014; Groom & Allen, 2014[Groom, C. R. & Allen, F. H. (2014). Angew. Chem. Int. Ed. Engl. 53, 662-671.]), only seven of these structures have substitution at the 1-position and an aryl group at the 2-position. Of these compounds, only three have a tert-butane­sulfinyl group [CSD refcodes CAVQOG (Zhong et al., 2005[Zhong, Y.-W., Dong, Y.-Z., Fang, K., Izumi, K., Xu, M.-H. & Lin, G.-Q. (2005). J. Am. Chem. Soc. 127, 11956-11957.]), FIZBIB (Jiang et al., 2014[Jiang, J.-L., Yao, M. & Lu, C.-D. (2014). Org. Lett. 16, 318-321.]) and WOBNEI (Buesking & Ellman, 2014[Buesking, A. W. & Ellman, J. A. (2014). Chem. Sci. 5, 1983-1987.])], and the other four contain p-toluene­sulfinyl groups [CSD refcodes PAQZIR (Zhao et al., 2005[Zhao, Y., Jiang, N., Chen, S., Peng, C., Zhang, X., Zou, Y., Zhang, S. & Wang, J. (2005). Tetrahedron, 61, 6546-6552.]), RUXZUG (Ghorai et al., 2010[Ghorai, M. K., Kumar, A. & Tiwari, D. P. (2010). J. Org. Chem. 75, 137-151.]), WADYOR (Fadlalla et al., 2010[Fadlalla, M. I., Friedrich, H. B., Maguire, G. E. M. & Omondi, B. (2010). Acta Cryst. E66, o3279-o3280.]) and SICSII (Guo et al., 2012[Guo, Y.-L., Bai, J.-F., Peng, L., Wang, L.-L., Jia, L.-N., Luo, X.-Y., Tian, F., Xu, X.-Y. & Wang, L.-X. (2012). Private communication (refcode SICSII). CCDC, Cambridge, England.])]. However, none of these seven compounds were synthesized by our method of inter­est.

5. Synthesis and crystallization

The starting sulfinamide, (R,E)-N-(2-(benz­yloxy)propyl­idene)-2-methyl­propane-2-sulfinamide, (3a), was prepared from S-ethyl lactate (Enders et al., 2002[Enders, D., von Berg, S., Jandeleit, B., Savall, B. M. & Roush, W. R. (2002). Org. Synth. 78, 177-182.]; Evans & Ellman, 2003[Evans, J. W. & Ellman, J. A. (2003). J. Org. Chem. 68, 9948-9957.]). Grignard reagents (4a) and (4b) were prepared from 2-bromoxylene and 2-bromo­mesitylene, respectively (Tilstam & Weinmann, 2002[Tilstam, U. & Weinmann, H. (2002). Org. Process Res. Dev. 6, 906-910.]). The synthesis of the title compounds is illustrated in Fig. 1[link].

General procedure

To an oven-dried 50 ml Schlenk flask equipped with a magnetic stirrer bar and a rubber septum, sulfinamide (3a) and toluene (20 ml) were added and the mixture was cooled to 195 K under nitro­gen. The Grignard reagent (4a) or (4b) in toluene was placed under positive nitro­gen pressure and was added to the Schlenk flask dropwise by cannula at 195 K. The reaction was stirred at 195 K and stopped when complete consumption of the imine was confirmed by thin-layer chromatography (30% ethyl acetate in hexa­nes, stained with ceric ammonium molybdate). The reaction was quenched with aqueous saturated sodium sulfate (1.5 ml), then the mixture was warmed to room temperature, dried over sodium sulfate, filtered through Celite, and the solvent was removed under reduced pressure. The ratio of diastereomers was determined by 1H NMR of the crude material, specifically by examining the amine (N—H) proton resonances. The chemical shifts of anti diastereomers like (1) and (6) were found around δ = 3.78 p.p.m., while those for syn diastereomers were found slightly further upfield at δ = 3.61 (mixture, see below) and 3.66 (5) p.p.m.. The crude viscous yellow oil was purified by column chromatography. Crystals suitable for single-crystal X-ray diffraction were obtained from slow evaporation of methanol solutions.

(RS)-N-[(1R,2S)-2-benz­yloxy-1-(2,6-di­methyl­phenyl)propyl]-2-methyl­propane-2-sulfinamide (1):

The reaction of sulfinamide (3a) (0.631 g, 2.36 mmol) with xylylmagnesium bromide [(4a), 3.80 equiv, 8.87 mmol], performed according to the general procedure, yielded a 2.5:1 ratio of diastereomers, (1) to (5), respectively (see Fig. 1[link]). The light-yellow oil was purified by column chromatography (100% diethyl ether) to yield a light-yellow solid (239 mg, 27%).

(1): m.p.: 346–348 K, 1H NMR (500 MHz, CDCl3): δ 1.20 (d, J = 0.3, 9H), 1.32 (d, J = 6.1, 3H), 2.36 (s, 3H), 2.43 (s, 3H), 3.71–3.70 (m, 1H), 3.99 (td, J = 6.7, 0.3, 1H), 4.27 (d, J = 11.8, 1H), 4.39 (d, J = 11.8, 1H), 4.92–4.89 (m, 1H), 6.96–6.94 (m, 1H), 7.02–7.01 (m, 3H), 7.08 (d, J = 7.6, 1H), 7.22 (d, J = 4.6, 3H). 13C NMR (126 MHz, CDCl3): δ 17.65, 21.62, 21.77, 22.71, 55.48, 59.01, 71.27, 76.41, 127.49, 127.60, 127.85, 128.35, 128.50, 130.43, 134.91, 137.22, 138.32, 138.57. IR (neat): 3271, 1084, 1041 cm−1. Analysis calculated for C22H31NO2S (%), 70.74 C, 8.36 H, 3.75 N, found (%) 70.99 C, 8.58 H, 3.66 N.

(RS)-N-[(1S,2R)-2-benz­yloxy-1-(2,4,6-tri­methyl­phenyl)propyl]-2-methyl­propane-2-sulfinamide (2):

The reaction of sulfinamide (3a) (0.757 g, 2.83 mmol), which contained an impurity (8%) of sulfinamide (3b), with mesitylmagnesium bromide [(4b), 3.00 equiv, 8.50 mmol] in toluene, performed according to the general procedure, yielded a mixture of anti and syn diastereomers. The light-yellow oil was purified by column chromatography (80% diethyl ether in hexa­nes) to yield two white solids. The first was the expected major product (6) (467 mg, 43%). The second (207 mg, 19%) was determined to be a mixture of diastereomers (based on 1H NMR) that contained (2) (confirmed by X-ray crystallography) and two others, likely (7) and (8) (see Fig. 1[link]). No further characterization or separation was performed on this mixture.

(6): 1H NMR (500 MHz, CDCl3): δ 1.17 (s, 9H), 1.29 (d, J = 6.1, 3H), 2.26 (s, 3H), 2.33 (s, 3H), 2.39 (s, 3H), 3.72–3.71 (m, 1H), 3.98–3.95 (m, 1H), 4.29 (d, J = 11.9, 1H), 4.39 (d, J = 11.8, 1H), 4.88–4.86 (m, 1H), 6.77 (s, 1H), 6.84 (s, 1H), 7.06 (d, J = 4.3, 2H), 7.22 (s, 3H). 13C NMR (126 MHz, CDCl3): δ 17.61, 20.97, 21.56, 21.65, 22.76, 55.44, 58.65, 58.67, 71.30, 76.66, 127.58, 127.88, 128.34, 129.38, 130.80, 131.22, 137.13, 138.45. IR (neat): 3271, 1057 cm−1. Analysis calculated for C23H33NO2S (%), 71.27 C, 8.58 H, 3.61 N, found (%) 70.55 C, 8.62 H, 3.49 N.

6. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 3[link]. For (1), the absolute configuration was determined using 4260 quotients, which gave a Flack parameter of 0.005 (12). The value obtained without Dobs(h) as a restraint was −0.02 (3), calculated from 5203 Friedel pairs. For (2), the absolute configuration was determined using 1713 quotients, which gave a Flack parameter of 0.03 (6). The value obtained without Dobs(h) as a restraint was −0.04 (8), calculated from 2882 Friedel pairs. In (2), the needle-shaped crystal diffracted weakly at higher angles. The cut-off resolution of 0.72 Å was chosen to maximize the number of enanti­omer-determining reflections, while limiting the inclusion of very weak high-angle data. The largest residual peak of 0.72 e Å−3 is located in the S1—C20 bond.

Table 3
Experimental details

  (1) (2)
Crystal data
Chemical formula C22H31NO2S C23H33NO2S
Mr 373.54 387.56
Crystal system, space group Orthorhombic, P212121 Monoclinic, P21
Temperature (K) 100 100
a, b, c (Å) 9.1567 (13), 10.2951 (15), 22.494 (3) 10.535 (3), 7.984 (2), 13.481 (4)
α, β, γ (°) 90, 90, 90 90, 103.519 (5), 90
V3) 2120.5 (5) 1102.5 (5)
Z 4 2
Radiation type Mo Kα Mo Kα
μ (mm−1) 0.17 0.16
Crystal size (mm) 0.40 × 0.25 × 0.20 0.50 × 0.14 × 0.10
 
Data collection
Diffractometer Bruker APEXII CCD Bruker SMART APEXII CCD platform
Absorption correction Multi-scan (SADABS; Bruker, 2014[Bruker (2014). APEX2, SAINT and SADABS. Bruker AXS, Inc., Madison, Wisconsin, USA.]) Multi-scan (SADABS; Bruker, 2014[Bruker (2014). APEX2, SAINT and SADABS. Bruker AXS, Inc., Madison, Wisconsin, USA.])
Tmin, Tmax 0.642, 0.748 0.564, 0.746
No. of measured, independent and observed [I > 2σ(I)] reflections 74315, 11731, 10413 18025, 6191, 4675
Rint 0.041 0.074
(sin θ/λ)max−1) 0.879 0.695
 
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.039, 0.096, 1.09 0.055, 0.126, 1.01
No. of reflections 11731 6191
No. of parameters 245 255
No. of restraints 0 1
H-atom treatment H atoms treated by a mixture of independent and constrained refinement H atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3) 0.40, −0.30 0.72, −0.32
Absolute structure Flack x determined using 4260 quotients [(I+)−(I)]/[(I+)+(I)] (Parsons et al., 2013[Parsons, S., Flack, H. D. & Wagner, T. (2013). Acta Cryst. B69, 249-259.]) Flack x determined using 1713 quotients [(I+)−(I)]/[(I+)+(I)] (Parsons et al., 2013[Parsons, S., Flack, H. D. & Wagner, T. (2013). Acta Cryst. B69, 249-259.])
Absolute structure parameter 0.005 (12) 0.03 (6)
Computer programs: APEX2 and SAINT (Bruker, 2014[Bruker (2014). APEX2, SAINT and SADABS. Bruker AXS, Inc., Madison, Wisconsin, USA.]), SHELXS2013, SHELXL2014 and SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]).

For both structures, the amine H atoms were located from difference Fourier maps and freely refined. The C-bound H atoms were placed geometrically and treated as riding with C—H = 0.95–1.00 Å and with Uiso(H) = 1.5Ueq(C) for methyl H atoms and = 1.2Ueq(C) for other H atoms.

Supporting information


Chemical context top

1,2-Amino alcohols are found in a variety of pharmaceutically active compounds (Lee & Kang, 2004) and have been used extensively as components of chiral ligands and auxiliaries in asymmetric synthesis (Ager et al., 1996; Pu & Yu, 2001). In order to develop new chiral ligands and as part of an advanced undergraduate laboratory course, we sought to make a series of 2-aryl-1-methyl-1,2-amino alcohols. The most straightforward synthesis of these compounds was reported by Ellman (Tang et al., 2001; Evans & Ellman, 2003). The method relies upon the chiral ammonia equivalent, 2-methyl-2-propane­sulfinamide (tert-butane­sulfinamide), which is readily available from a variety of commercial sources or easily synthesized on scale (Weix et al., 2005). In the original Ellman report, the absolute configuration of the products was determined by deprotection of the amine and alcohol, cyclization to form the corresponding oxazolidinone, and correlation of the 1H NMR spectra with the literature (Zietlow & Steckhan, 1994).

We now report herein on the syntheses and structures of two different but related protected 1,2-amino alcohols, (1) and (2), from the addition of an aryl­magnesium bromide to an N-(tert-butane­sulfinyl imine (Evans & Ellman, 2003). The reaction of imine (3a) with xylylmagnesium bromide, (4a) (see Fig. 1) resulted in a mixture of amino alcohol products from which the major product of the reaction, (1), was isolated in 27% yield after chromatographic separation of the diastereomers. The stereochemistry of this major product was confirmed by X-ray diffraction and the result is consistent with the sense of induction reported by Evans & Ellman (2003).

The analogous reaction with mesitylmagnesium bromide, (4b), also resulted in a mixture of products, from which the major product, (6), could be isolated in 43% yield. A mixture of other diastereomers was also isolated, from which a crystal suitable for X-ray diffraction was grown. Unexpectedly, X-ray analysis showed this crystal to be (2), a product that could only have derived from a diastereomerically different isomer of (3a). Upon further investigation, we discovered that the starting material, which we had assumed was pure (3a), contained the minor diastereomer, (3b), in about 8% (determined by 1H NMR; Fontenelle et al., 2014), which had formed due to racemization in the synthesis of (3a). Based on the work of Evans & Ellman (2003), it was deduced that (2) is the minor product expected from the reaction of (3b) with an aryl­magnesium bromide. Although no further separations were performed on this mixture that contained (2), it follows that the other diastereomers present were (7), the minor product from the reaction with (3a), and (8), the major product from the reaction with the slight impurity of (3b).

Structural commentary top

The molecular structures of compounds (1) and (2) are illustrated in Figs. 2 and 3, respectively. The essential difference in the conformation of the two compounds is that the phenyl ring (C5–C10) is inclined to the benzene ring (C11–C16) by 28.52 (7)° in (1) and by 44.65 (19)° in (2).

Supra­molecular features top

In the crystals of both (1) and (2), chains are formed via inter­molecular hydrogen bonding (Tables 1 and 2). In (1), molecules are linked along the [100] direction by a combination of classical (N—H···OS) and non-classical (C—H···OS) hydrogen bonds (Table 1 and Fig. 4). In (2), molecules are linked along the [010] direction also by classical (N—H···OS) and non-classical (C—H···OS) hydrogen bonds (Table 2 and Fig. 5).

Database survey top

Although there are 78 structures of N-sulfinyl-protected 1,2-amino alcohols in the Cambridge Structural Database (CSD, Version 5.35, last update May 2014; Groom & Allen, 2014), only seven of these structures have substitution at the 1-position and an aryl group at the 2-position. Of these compounds, only three have a tert-butane­sulfinyl group [CSD refcodes CAVQOG (Zhong et al., 2005), FIZBIB (Jiang et al., 2014) and WOBNEI (Buesking & Ellman, 2014)], and the other four contain p-toluene­sulfinyl groups [CSD refcodes PAQZIR (Zhao et al., 2005), RUXZUG (Ghorai et al., 2010), WADYOR (Fadlalla et al., 2010) and SICSII (Guo et al., 2012)]. However, none of these seven compounds were synthesized by our method of inter­est.

Synthesis and crystallization top

\ The starting sulfinamide, (R,E)-N-(2-(benzyl­oxy)propyl­idene)-2-methyl­propane-2-\ sulfinamide, (3a), was prepared from S-ethyl la­ctate (Enders et al., 2002; Evans & Ellman, 2003). Grignard reagents (4a) and (4b) were prepared from 2-bromoxylene and 2-bromo­mesitylene, respectively (Tilstam & Weinmann, 2002). The synthesis of the title compounds is illustrated in Fig. 1.

General procedure

To an oven-dried 50 ml Schlenk flask equipped with a magnetic stirrer bar and a rubber septum, sulfinamide (3a) and toluene (20 ml) were added and the mixture was cooled to 195 K under nitro­gen. The Grignard reagent (4a) or (4b) in toluene was placed under positive nitro­gen pressure and was added to the Schlenk flask dropwise by cannula at 195 K. The reaction was stirred at 195 K and stopped when complete consumption of the imine was confirmed by thin-layer chromatography (30% ethyl acetate in hexanes, stained with ceric ammonium molybdate). The reaction was quenched with aqueous saturated sodium sulfate (1.5 ml), then the mixture was warmed to room temperature, dried over sodium sulfate, filtered through Celite, and the solvent was removed under reduced pressure. The ratio of diastereomers was determined by 1H NMR of the crude material, specifically by examining the amine (N—H) proton resonances. The chemical shifts of anti diastereomers like (1) and (6) were found around δ = 3.78 p.p.m., while those for syn diastereomers were found slightly further upfield at δ = 3.61 (mixture, see below) and 3.66 (5) p.p.m.. The crude viscous yellow oil was purified by column chromatography. Crystals suitable for single-crystal X-ray diffraction were obtained from slow evaporation of methanol solutions.

(RS)-N-\ [(1R,2S)-2-benzyl­oxy-1-(2,6-\ di­methyl­phenyl)­propyl]-2-methyl­propane-2-sulfinamide (1):

The reaction of sulfinamide (3a) (0.631 g, 2.36 mmol) with xylylmagnesium bromide [(4a), 3.80 equiv, 8.87 mmol], performed according to the general procedure, yielded a 2.5:1 ratio of diastereomers, (1) to (5), respectively (see Fig. 1). The light-yellow oil was purified by column chromatography (100% di­ethyl ether) to yield a light-yellow solid (239 mg, 27%).

(1): m.p.: 346–348 K, 1H NMR (500 MHz, CDCl3): δ 1.20 (d, J = 0.3, 9H), 1.32 (d, J = 6.1, 3H), 2.36 (s, 3H), 2.43 (s, 3H), 3.71–3.70 (m, 1H), 3.99 (td, J = 6.7, 0.3, 1H), 4.27 (d, J = 11.8, 1H), 4.39 (d, J = 11.8, 1H), 4.92–4.89 (m, 1H), 6.96–6.94 (m, 1H), 7.02–7.01 (m, 3H), 7.08 (d, J = 7.6, 1H), 7.22 (d, J = 4.6, 3H). 13C NMR (126 MHz, CDCl3): δ 17.65, 21.62, 21.77, 22.71, 55.48, 59.01, 71.27, 76.41, 127.49, 127.60, 127.85, 128.35, 128.50, 130.43, 134.91, 137.22, 138.32, 138.57. IR (neat): 3271, 1084, 1041 cm-1. Analysis calculated for C22H31NO2S (%), 70.74 C, 8.36 H, 3.75 N, found (%) 70.99 C, 8.58 H, 3.66 N.

(RS)-N-\ [(1S,2R)-2-benzyl­oxy-1-(2,4,6-\ tri­methyl­phenyl)­propyl]-2-methyl­propane-2-sulfinamide (2):

The reaction of sulfinamide (3a) (0.757 g, 2.83 mmol), which contained an impurity (8%) of sulfinamide (3b), with mesitylmagnesium bromide [(4b), 3.00 equiv, 8.50 mmol] in toluene, performed according to the general procedure, yielded a mixture of anti and syn diastereomers. The light-yellow oil was purified by column chromatography (80% di­ethyl ether in hexanes) to yield two white solids. The first was the expected major product (6) (467 mg, 43%). The second (207 mg, 19%) was determined to be a mixture of diastereomers (based on 1H NMR) that contained (2) (confirmed by X-ray crystallography) and two others, likely (7) and (8) (see Fig. 1). No further characterization or separation was performed on this mixture.

(6): 1H NMR (500 MHz, CDCl3): δ 1.17 (s, 9H), 1.29 (d, J = 6.1, 3H), 2.26 (s, 3H), 2.33 (s, 3H), 2.39 (s, 3H), 3.72–3.71 (m, 1H), 3.98–3.95 (m, 1H), 4.29 (d, J = 11.9, 1H), 4.39 (d, J = 11.8, 1H), 4.88–4.86 (m, 1H), 6.77 (s, 1H), 6.84 (s, 1H), 7.06 (d, J = 4.3, 2H), 7.22 (s, 3H). 13C NMR (126 MHz, CDCl3): δ 17.61, 20.97, 21.56, 21.65, 22.76, 55.44, 58.65, 58.67, 71.30, 76.66, 127.58, 127.88, 128.34, 129.38, 130.80, 131.22, 137.13, 138.45. IR (neat): 3271, 1057 cm-1. Analysis calculated for C23H33NO2S (%), 71.27 C, 8.58 H, 3.61 N, found (%) 70.55 C, 8.62 H, 3.49 N.

Refinement top

Crystal data, data collection and structure refinement details are summarized in Table 3. For (1), the absolute configuration was determined using 4260 quotients, which gave a Flack parameter of 0.005 (12). The value obtained without Dobs(h) as a restraint was -0.02 (3), calculated from 5203 Friedel pairs. For (2), the absolute configuration was determined using 1713 quotients, which gave a Flack parameter of 0.03 (6). The value obtained without Dobs(h) as a restraint was -0.04 (8), calculated from 2882 Friedel pairs. In (2), the needle-shaped crystal diffracted weakly at higher angles. The cut-off resolution of 0.72 Å was chosen to maximize the number of enanti­omer-determining reflections, while limiting the inclusion of very weak high-angle data. The largest residual peak of 0.72 e Å-3 is located in the S1—C20 bond.

For both structures, the amine H atoms were located from difference Fourier maps and freely refined. The C-bound H atoms were placed geometrically and treated as riding with C—H = 0.95–1.00 Å and with Uiso(H) = 1.5Ueq(C) for methyl H atoms and = 1.2Ueq(C) for other H atoms.

Related literature top

For related literature, see: Ager et al. (1996); Allen (2002); Buesking & Ellman (2014); Enders et al. (2002); Evans & Ellman (2003); Fadlalla et al. (2010); Fontenelle et al. (2014); Ghorai et al. (2010); Guo et al. (2012); Jiang et al. (2014); Lee & Kang (2004); Pu & Yu (2001); Tang et al. (2001); Tilstam & Weinmann (2002); Weix et al. (2005); Zhao et al. (2005); Zhong et al. (2005); Zietlow & Steckhan (1994).

Computing details top

For both compounds, data collection: APEX2 (Bruker, 2014); cell refinement: SAINT (Bruker, 2014); data reduction: SAINT (Bruker, 2014); program(s) used to solve structure: SHELXS2013 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
(Top) Reaction scheme depicting the synthesis of (1) and (5) from (3a), for which (1) is the major product of the reaction. (Bottom) Reaction scheme depicting the synthesis of (6) and (7) from (3a), and (8) and (2) from (3b), for which (6) is the major product of the reaction from (3a), and (8) is the major product from (3b).

The molecular structure of compound (1), with atom labelling. Displacement ellipsoids are drawn at the 50% probability level.

The molecular structure of compound (2), with atom labelling. Displacement ellipsoids are drawn at the 50% probability level.

A partial view of the crystal packing of compound (1), illustrating the formation of the hydrogen-bonded chains along [100] (hydrogen bonds are shown as dashed lines; see Table 1 for details). Displacement ellipsoids are drawn at the 50% probability level.

A partial view of the crystal packing of compound (2), illustrating the formation of the hydrogen-bonded chains along [010] (hydrogen bonds are shown as dashed lines; see Table 2 for details). Displacement ellipsoids are drawn at the 50% probability level.
(1) (RS)-N-[(1R,2S)-2-Benzyloxy-1-(2,6-dimethylphenyl)propyl]-2-methylpropane-2-sulfinamide top
Crystal data top
C22H31NO2SDx = 1.170 Mg m3
Mr = 373.54Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, P212121Cell parameters from 3707 reflections
a = 9.1567 (13) Åθ = 2.4–38.1°
b = 10.2951 (15) ŵ = 0.17 mm1
c = 22.494 (3) ÅT = 100 K
V = 2120.5 (5) Å3Block, colourless
Z = 40.40 × 0.25 × 0.20 mm
F(000) = 808
Data collection top
Bruker APEXII CCD
diffractometer
10413 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.041
ϕ and ω scansθmax = 38.7°, θmin = 1.8°
Absorption correction: multi-scan
(SADABS; Bruker, 2014)
h = 1615
Tmin = 0.642, Tmax = 0.748k = 1717
74315 measured reflectionsl = 3939
11731 independent reflections
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.039H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.096 w = 1/[σ2(Fo2) + (0.0463P)2 + 0.2202P]
where P = (Fo2 + 2Fc2)/3
S = 1.09(Δ/σ)max < 0.001
11731 reflectionsΔρmax = 0.40 e Å3
245 parametersΔρmin = 0.30 e Å3
0 restraintsAbsolute structure: Flack x determined using 4260 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons et al., 2013)
Primary atom site location: structure-invariant direct methodsAbsolute structure parameter: 0.005 (12)
Crystal data top
C22H31NO2SV = 2120.5 (5) Å3
Mr = 373.54Z = 4
Orthorhombic, P212121Mo Kα radiation
a = 9.1567 (13) ŵ = 0.17 mm1
b = 10.2951 (15) ÅT = 100 K
c = 22.494 (3) Å0.40 × 0.25 × 0.20 mm
Data collection top
Bruker APEXII CCD
diffractometer
11731 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2014)
10413 reflections with I > 2σ(I)
Tmin = 0.642, Tmax = 0.748Rint = 0.041
74315 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.039H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.096Δρmax = 0.40 e Å3
S = 1.09Δρmin = 0.30 e Å3
11731 reflectionsAbsolute structure: Flack x determined using 4260 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons et al., 2013)
245 parametersAbsolute structure parameter: 0.005 (12)
0 restraints
Special details top

Experimental. Dry solvents were prepared from ACS grade, inhibitor free solvents by passage through activated molecular sieves in an Innovative Technology solvent purification system. CDCl3 was purchased from Cambridge Isotope Laboratories, Inc., and dried over molecular sieves. 1H and 13C NMR spectra were recorded on an Avance 500 MHz spectrometer with residual protiated solvent as a reference.

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. The amine H atom was found from the difference Fourier map and refined freely. All other H atoms were placed geometrically and treated as riding atoms: methine, C—H = 1.00 Å with Uiso(H) = 1.2Ueq(C), methylene, C—H = 0.99 Å with Uiso(H) = 1.2Ueq(C), methyl, C—H = 0.98 Å with Uiso(H) = 1.5Ueq(C), sp2, C—H = 0.95 Å with Uiso(H) = 1.2Ueq(C).

The absolute configuration was deterimined using 4260 quotients, which gave a Flack parameter of 0.005 (12) (Parsons and Flack, 2004, Parsons et al., 2013). The value obtained without Dobs(h) as a restraint was -0.02 (3), calculated from 5203 Friedel pairs (Flack, 1983).

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
S10.79149 (3)0.10142 (3)0.03041 (2)0.01557 (5)
O10.91190 (11)0.06660 (10)0.18104 (4)0.02226 (18)
O20.68782 (10)0.21396 (10)0.02920 (4)0.02241 (17)
N10.92290 (11)0.11541 (10)0.01896 (4)0.01623 (16)
H10.977 (2)0.1819 (19)0.0167 (8)0.021 (4)*
C10.89269 (12)0.05350 (11)0.07694 (5)0.01571 (17)
H1A0.78430.05580.08230.019*
C20.95786 (13)0.13364 (12)0.12820 (5)0.01660 (18)
H2A1.06690.13370.12550.020*
C30.90089 (15)0.27252 (13)0.12894 (6)0.0217 (2)
H3A0.93770.31910.09400.033*
H3B0.79390.27160.12810.033*
H3C0.93440.31620.16520.033*
C41.00691 (18)0.08699 (16)0.23019 (6)0.0281 (3)
H4A1.02920.18090.23320.034*
H4B0.95590.06090.26710.034*
C51.14836 (16)0.01255 (14)0.22566 (5)0.0225 (2)
C61.14793 (17)0.11740 (14)0.20832 (6)0.0253 (2)
H6A1.05850.15820.19770.030*
C71.2770 (2)0.18760 (17)0.20640 (7)0.0326 (3)
H7A1.27550.27650.19510.039*
C81.40849 (19)0.12847 (19)0.22088 (7)0.0349 (4)
H8A1.49680.17690.21980.042*
C91.4105 (2)0.0017 (2)0.23699 (8)0.0382 (4)
H9A1.50040.04280.24630.046*
C101.2812 (2)0.07163 (15)0.23950 (7)0.0319 (3)
H10A1.28310.16060.25070.038*
C110.93628 (12)0.08950 (11)0.07699 (5)0.01664 (18)
C120.82885 (15)0.18286 (13)0.09100 (6)0.0229 (2)
C130.86506 (17)0.31517 (14)0.09039 (7)0.0290 (3)
H13A0.79340.37780.10090.035*
C141.00387 (18)0.35576 (14)0.07467 (8)0.0300 (3)
H14A1.02650.44580.07330.036*
C151.10962 (16)0.26432 (13)0.06090 (7)0.0247 (2)
H15A1.20460.29250.04990.030*
C161.07903 (13)0.13087 (11)0.06295 (5)0.01810 (19)
C170.67364 (17)0.14536 (17)0.10624 (9)0.0355 (4)
H17A0.61800.22340.11660.053*
H17B0.67400.08550.14010.053*
H17C0.62830.10280.07190.053*
C181.20616 (14)0.04049 (12)0.05286 (6)0.0209 (2)
H18A1.17040.04210.03680.031*
H18B1.25640.02480.09070.031*
H18C1.27430.08000.02460.031*
C190.90048 (13)0.12273 (13)0.09851 (5)0.0195 (2)
C201.01500 (19)0.01501 (19)0.09980 (7)0.0349 (4)
H20A1.08830.03120.06890.052*
H20B0.96770.06890.09250.052*
H20C1.06250.01350.13880.052*
C220.78986 (16)0.10520 (16)0.14911 (5)0.0259 (2)
H22A0.71450.17250.14630.039*
H22B0.84010.11260.18740.039*
H22C0.74430.01930.14600.039*
C230.96837 (16)0.25766 (16)0.10044 (6)0.0267 (3)
H23A0.89230.32320.09410.040*
H23B1.04230.26510.06910.040*
H23C1.01420.27150.13930.040*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
S10.01487 (10)0.01513 (10)0.01672 (10)0.00088 (9)0.00119 (9)0.00003 (9)
O10.0245 (4)0.0271 (5)0.0152 (3)0.0001 (3)0.0034 (3)0.0033 (3)
O20.0182 (4)0.0259 (4)0.0231 (4)0.0091 (3)0.0017 (3)0.0013 (3)
N10.0168 (4)0.0165 (4)0.0154 (3)0.0027 (3)0.0016 (3)0.0019 (3)
C10.0152 (4)0.0166 (4)0.0154 (4)0.0020 (3)0.0009 (3)0.0014 (3)
C20.0169 (4)0.0184 (5)0.0146 (4)0.0004 (3)0.0011 (3)0.0000 (3)
C30.0229 (5)0.0184 (5)0.0239 (5)0.0019 (4)0.0007 (4)0.0023 (4)
C40.0382 (7)0.0317 (7)0.0144 (4)0.0072 (6)0.0002 (4)0.0015 (4)
C50.0301 (6)0.0240 (6)0.0135 (4)0.0004 (5)0.0017 (4)0.0037 (4)
C60.0323 (6)0.0226 (6)0.0209 (5)0.0008 (5)0.0010 (4)0.0038 (4)
C70.0416 (8)0.0305 (7)0.0257 (6)0.0083 (6)0.0018 (6)0.0029 (5)
C80.0314 (7)0.0483 (10)0.0250 (6)0.0096 (7)0.0002 (5)0.0110 (6)
C90.0316 (7)0.0491 (10)0.0340 (8)0.0079 (7)0.0110 (6)0.0155 (7)
C100.0405 (8)0.0281 (7)0.0271 (6)0.0050 (6)0.0128 (6)0.0057 (5)
C110.0179 (4)0.0146 (4)0.0174 (4)0.0029 (3)0.0008 (3)0.0011 (3)
C120.0229 (5)0.0199 (5)0.0260 (5)0.0079 (4)0.0033 (4)0.0004 (4)
C130.0312 (7)0.0193 (6)0.0365 (7)0.0105 (5)0.0017 (6)0.0015 (5)
C140.0348 (7)0.0145 (5)0.0406 (8)0.0033 (5)0.0023 (6)0.0007 (5)
C150.0250 (6)0.0156 (5)0.0336 (6)0.0002 (4)0.0010 (5)0.0000 (4)
C160.0190 (5)0.0144 (4)0.0209 (5)0.0013 (3)0.0002 (4)0.0014 (3)
C170.0242 (6)0.0292 (7)0.0531 (9)0.0119 (5)0.0154 (6)0.0066 (7)
C180.0168 (4)0.0177 (5)0.0283 (5)0.0006 (4)0.0026 (4)0.0021 (4)
C190.0182 (4)0.0241 (6)0.0162 (4)0.0074 (4)0.0004 (3)0.0003 (4)
C200.0365 (8)0.0441 (9)0.0242 (6)0.0263 (7)0.0023 (5)0.0011 (6)
C220.0270 (5)0.0338 (6)0.0169 (4)0.0053 (6)0.0028 (4)0.0038 (4)
C230.0219 (5)0.0349 (7)0.0232 (5)0.0027 (5)0.0020 (4)0.0066 (5)
Geometric parameters (Å, º) top
S1—O21.4980 (9)C11—C161.4106 (17)
S1—N11.6436 (10)C11—C121.4109 (16)
S1—C191.8415 (12)C12—C131.402 (2)
O1—C41.4225 (17)C12—C171.512 (2)
O1—C21.4374 (14)C13—C141.384 (2)
N1—C11.4778 (14)C13—H13A0.9500
N1—H10.84 (2)C14—C151.386 (2)
C1—C111.5253 (17)C14—H14A0.9500
C1—C21.5383 (16)C15—C161.4029 (18)
C1—H1A1.0000C15—H15A0.9500
C2—C31.5221 (18)C16—C181.5075 (17)
C2—H2A1.0000C17—H17A0.9800
C3—H3A0.9800C17—H17B0.9800
C3—H3B0.9800C17—H17C0.9800
C3—H3C0.9800C18—H18A0.9800
C4—C51.508 (2)C18—H18B0.9800
C4—H4A0.9900C18—H18C0.9800
C4—H4B0.9900C19—C231.522 (2)
C5—C61.394 (2)C19—C201.5266 (18)
C5—C101.395 (2)C19—C221.5342 (17)
C6—C71.386 (2)C20—H20A0.9800
C6—H6A0.9500C20—H20B0.9800
C7—C81.388 (3)C20—H20C0.9800
C7—H7A0.9500C22—H22A0.9800
C8—C91.388 (3)C22—H22B0.9800
C8—H8A0.9500C22—H22C0.9800
C9—C101.387 (3)C23—H23A0.9800
C9—H9A0.9500C23—H23B0.9800
C10—H10A0.9500C23—H23C0.9800
O2—S1—N1112.57 (5)C13—C12—C11119.66 (13)
O2—S1—C19105.45 (5)C13—C12—C17118.20 (12)
N1—S1—C1998.91 (5)C11—C12—C17122.14 (13)
C4—O1—C2113.13 (10)C14—C13—C12120.87 (13)
C1—N1—S1114.92 (8)C14—C13—H13A119.6
C1—N1—H1120.8 (13)C12—C13—H13A119.6
S1—N1—H1117.1 (13)C13—C14—C15119.59 (13)
N1—C1—C11111.58 (9)C13—C14—H14A120.2
N1—C1—C2110.96 (9)C15—C14—H14A120.2
C11—C1—C2114.56 (9)C14—C15—C16121.23 (13)
N1—C1—H1A106.4C14—C15—H15A119.4
C11—C1—H1A106.4C16—C15—H15A119.4
C2—C1—H1A106.4C15—C16—C11119.22 (11)
O1—C2—C3109.98 (10)C15—C16—C18116.44 (11)
O1—C2—C1104.41 (9)C11—C16—C18124.26 (11)
C3—C2—C1112.28 (10)C12—C17—H17A109.5
O1—C2—H2A110.0C12—C17—H17B109.5
C3—C2—H2A110.0H17A—C17—H17B109.5
C1—C2—H2A110.0C12—C17—H17C109.5
C2—C3—H3A109.5H17A—C17—H17C109.5
C2—C3—H3B109.5H17B—C17—H17C109.5
H3A—C3—H3B109.5C16—C18—H18A109.5
C2—C3—H3C109.5C16—C18—H18B109.5
H3A—C3—H3C109.5H18A—C18—H18B109.5
H3B—C3—H3C109.5C16—C18—H18C109.5
O1—C4—C5113.43 (11)H18A—C18—H18C109.5
O1—C4—H4A108.9H18B—C18—H18C109.5
C5—C4—H4A108.9C23—C19—C20112.44 (13)
O1—C4—H4B108.9C23—C19—C22110.84 (11)
C5—C4—H4B108.9C20—C19—C22110.73 (11)
H4A—C4—H4B107.7C23—C19—S1110.71 (9)
C6—C5—C10118.92 (14)C20—C19—S1107.55 (9)
C6—C5—C4120.28 (13)C22—C19—S1104.21 (9)
C10—C5—C4120.80 (13)C19—C20—H20A109.5
C7—C6—C5120.45 (15)C19—C20—H20B109.5
C7—C6—H6A119.8H20A—C20—H20B109.5
C5—C6—H6A119.8C19—C20—H20C109.5
C6—C7—C8120.25 (15)H20A—C20—H20C109.5
C6—C7—H7A119.9H20B—C20—H20C109.5
C8—C7—H7A119.9C19—C22—H22A109.5
C7—C8—C9119.74 (16)C19—C22—H22B109.5
C7—C8—H8A120.1H22A—C22—H22B109.5
C9—C8—H8A120.1C19—C22—H22C109.5
C10—C9—C8120.05 (16)H22A—C22—H22C109.5
C10—C9—H9A120.0H22B—C22—H22C109.5
C8—C9—H9A120.0C19—C23—H23A109.5
C9—C10—C5120.57 (15)C19—C23—H23B109.5
C9—C10—H10A119.7H23A—C23—H23B109.5
C5—C10—H10A119.7C19—C23—H23C109.5
C16—C11—C12119.36 (11)H23A—C23—H23C109.5
C16—C11—C1122.26 (10)H23B—C23—H23C109.5
C12—C11—C1118.37 (11)
O2—S1—N1—C192.54 (9)N1—C1—C11—C12123.09 (11)
C19—S1—N1—C1156.53 (9)C2—C1—C11—C12109.78 (12)
S1—N1—C1—C1186.77 (10)C16—C11—C12—C130.43 (19)
S1—N1—C1—C2144.18 (8)C1—C11—C12—C13178.90 (12)
C4—O1—C2—C385.24 (13)C16—C11—C12—C17179.78 (14)
C4—O1—C2—C1154.11 (10)C1—C11—C12—C170.45 (19)
N1—C1—C2—O1176.40 (9)C11—C12—C13—C141.7 (2)
C11—C1—C2—O156.15 (12)C17—C12—C13—C14177.64 (16)
N1—C1—C2—C357.29 (13)C12—C13—C14—C151.7 (2)
C11—C1—C2—C3175.25 (10)C13—C14—C15—C160.4 (2)
C2—O1—C4—C574.91 (15)C14—C15—C16—C112.6 (2)
O1—C4—C5—C644.88 (17)C14—C15—C16—C18174.29 (13)
O1—C4—C5—C10136.05 (14)C12—C11—C16—C152.54 (18)
C10—C5—C6—C71.68 (19)C1—C11—C16—C15176.77 (11)
C4—C5—C6—C7177.41 (12)C12—C11—C16—C18174.06 (12)
C5—C6—C7—C81.0 (2)C1—C11—C16—C186.63 (18)
C6—C7—C8—C90.4 (2)O2—S1—C19—C2353.16 (10)
C7—C8—C9—C101.0 (2)N1—S1—C19—C2363.36 (9)
C8—C9—C10—C50.3 (2)O2—S1—C19—C20176.36 (10)
C6—C5—C10—C91.0 (2)N1—S1—C19—C2059.85 (11)
C4—C5—C10—C9178.05 (13)O2—S1—C19—C2266.06 (10)
N1—C1—C11—C1656.23 (14)N1—S1—C19—C22177.43 (9)
C2—C1—C11—C1670.90 (14)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O2i0.84 (2)2.23 (2)3.0039 (15)152.8 (7)
C18—H18A···O2i0.982.523.4077 (17)150
C23—H23B···O2i0.982.593.5534 (17)167
Symmetry code: (i) x+1/2, y+1/2, z.
(2) (RS)-N-[(1S,2R)-2-Benzyloxy-1-(2,4,6-trimethylphenyl)propyl]-2-methylpropane-2-sulfinamide top
Crystal data top
C23H33NO2SF(000) = 420
Mr = 387.56Dx = 1.167 Mg m3
Monoclinic, P21Mo Kα radiation, λ = 0.71073 Å
a = 10.535 (3) ÅCell parameters from 4086 reflections
b = 7.984 (2) Åθ = 2.2–28.7°
c = 13.481 (4) ŵ = 0.16 mm1
β = 103.519 (5)°T = 100 K
V = 1102.5 (5) Å3Needle, colorless
Z = 20.50 × 0.14 × 0.10 mm
Data collection top
Bruker SMART APEXII CCD platform
diffractometer
4675 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.074
ω scansθmax = 29.6°, θmin = 2.0°
Absorption correction: multi-scan
(SADABS; Bruker, 2014)
h = 1414
Tmin = 0.564, Tmax = 0.746k = 1111
18025 measured reflectionsl = 1818
6191 independent reflections
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.055H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.126 w = 1/[σ2(Fo2) + (0.0563P)2]
where P = (Fo2 + 2Fc2)/3
S = 1.01(Δ/σ)max < 0.001
6191 reflectionsΔρmax = 0.72 e Å3
255 parametersΔρmin = 0.32 e Å3
1 restraintAbsolute structure: Flack x determined using 1713 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons et al., 2013)
Primary atom site location: structure-invariant direct methodsAbsolute structure parameter: 0.03 (6)
Crystal data top
C23H33NO2SV = 1102.5 (5) Å3
Mr = 387.56Z = 2
Monoclinic, P21Mo Kα radiation
a = 10.535 (3) ŵ = 0.16 mm1
b = 7.984 (2) ÅT = 100 K
c = 13.481 (4) Å0.50 × 0.14 × 0.10 mm
β = 103.519 (5)°
Data collection top
Bruker SMART APEXII CCD platform
diffractometer
6191 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2014)
4675 reflections with I > 2σ(I)
Tmin = 0.564, Tmax = 0.746Rint = 0.074
18025 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.055H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.126Δρmax = 0.72 e Å3
S = 1.01Δρmin = 0.32 e Å3
6191 reflectionsAbsolute structure: Flack x determined using 1713 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons et al., 2013)
255 parametersAbsolute structure parameter: 0.03 (6)
1 restraint
Special details top

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. The amine H atom was found from the difference Fourier map and refined freely. All other H atoms were placed geometrically and treated as riding atoms: methine, C—H = 1.00 Å with Uiso(H) = 1.2Ueq(C), methylene, C—H = 0.99 Å with Uiso(H) = 1.2Ueq(C), methyl, C—H = 0.98 Å with Uiso(H) = 1.5Ueq(C), sp2, C—H = 0.95 Å with Uiso(H) = 1.2Ueq(C).

The absolute configuration was deterimined using 1713 quotients, which gave a Flack parameter of 0.03 (6) (Parsons and Flack, 2004, Parsons et al., 2013). The value obtained without Dobs(h) as a restraint was -0.04 (8), calculated from 2882 Friedel pairs (Flack, 1983).

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
S10.14253 (7)0.70038 (11)0.52944 (5)0.01937 (18)
O10.1200 (3)0.7675 (3)0.79000 (17)0.0277 (6)
O20.1009 (2)0.5256 (3)0.54810 (18)0.0255 (5)
N10.0861 (3)0.8363 (4)0.6010 (2)0.0193 (6)
H10.029 (4)0.895 (5)0.565 (3)0.029 (11)*
C10.0582 (3)0.7907 (4)0.7007 (2)0.0187 (7)
H1A0.07580.66810.71070.022*
C20.0893 (4)0.8173 (5)0.6958 (2)0.0228 (7)
H2A0.11210.93800.68220.027*
C30.1748 (3)0.7098 (6)0.6136 (2)0.0281 (7)
H3A0.26590.71820.61870.042*
H3B0.14620.59290.62280.042*
H3C0.16750.74900.54630.042*
C40.1156 (4)0.8932 (5)0.8670 (3)0.0309 (9)
H4A0.02380.92830.89350.037*
H4B0.14650.84340.92430.037*
C50.1973 (4)1.0465 (5)0.8290 (3)0.0277 (8)
C60.1330 (4)1.1992 (6)0.8314 (3)0.0399 (9)
H6A0.04141.20500.85870.048*
C70.2017 (6)1.3429 (6)0.7941 (4)0.0542 (14)
H7A0.15751.44670.79490.065*
C80.3341 (6)1.3334 (6)0.7562 (3)0.0516 (14)
H8A0.38121.43060.72840.062*
C90.4009 (5)1.1822 (8)0.7580 (3)0.0538 (14)
H9A0.49311.17770.73420.065*
C100.3300 (4)1.0372 (6)0.7954 (3)0.0375 (10)
H10A0.37390.93370.79720.045*
C110.1486 (3)0.8807 (4)0.7901 (2)0.0191 (7)
C120.2023 (4)0.7877 (4)0.8796 (2)0.0203 (7)
C130.2873 (3)0.8671 (5)0.9617 (2)0.0238 (7)
H13A0.32290.80431.02160.029*
C140.3208 (4)1.0342 (5)0.9582 (2)0.0276 (8)
C150.2652 (3)1.1243 (5)0.8705 (3)0.0253 (8)
H15A0.28661.23950.86720.030*
C160.1790 (3)1.0514 (4)0.7869 (2)0.0196 (7)
C170.1703 (4)0.6060 (5)0.8916 (3)0.0264 (8)
H17A0.22460.56300.95570.040*
H17B0.18760.54160.83430.040*
H17C0.07800.59530.89270.040*
C180.4126 (4)1.1175 (6)1.0483 (3)0.0416 (11)
H18A0.49201.04991.06950.062*
H18B0.36961.12681.10510.062*
H18C0.43561.22951.02850.062*
C190.1231 (4)1.1646 (4)0.6973 (2)0.0254 (8)
H19A0.13321.28170.71940.038*
H19B0.03031.13940.67120.038*
H19C0.16971.14590.64330.038*
C200.3203 (3)0.7019 (6)0.5841 (2)0.0256 (7)
C210.3559 (4)0.6297 (6)0.6915 (3)0.0344 (9)
H21A0.45100.61970.71410.052*
H21B0.31600.51880.69160.052*
H21C0.32360.70410.73800.052*
C220.3660 (4)0.8809 (6)0.5811 (4)0.0463 (12)
H22A0.46150.88460.60180.069*
H22B0.32920.94930.62780.069*
H22C0.33680.92470.51160.069*
C230.3749 (4)0.5895 (7)0.5121 (3)0.0415 (11)
H23A0.47050.58920.53290.062*
H23B0.34690.63210.44220.062*
H23C0.34220.47510.51500.062*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
S10.0237 (4)0.0206 (4)0.0128 (3)0.0007 (4)0.0020 (3)0.0017 (4)
O10.0448 (16)0.0204 (13)0.0200 (12)0.0009 (11)0.0122 (11)0.0008 (10)
O20.0313 (14)0.0179 (13)0.0265 (12)0.0014 (10)0.0053 (10)0.0064 (10)
N10.0276 (16)0.0165 (14)0.0120 (12)0.0023 (12)0.0010 (11)0.0034 (11)
C10.0311 (18)0.0125 (16)0.0119 (13)0.0027 (13)0.0042 (13)0.0000 (12)
C20.0339 (19)0.0198 (17)0.0145 (14)0.0023 (14)0.0055 (13)0.0005 (13)
C30.0316 (18)0.0297 (19)0.0234 (15)0.0088 (19)0.0072 (13)0.0046 (18)
C40.041 (2)0.029 (2)0.0231 (18)0.0047 (17)0.0093 (15)0.0058 (15)
C50.042 (2)0.026 (2)0.0195 (16)0.0040 (17)0.0152 (15)0.0025 (15)
C60.058 (2)0.030 (2)0.039 (2)0.002 (2)0.0265 (18)0.005 (2)
C70.094 (4)0.035 (3)0.043 (3)0.012 (3)0.033 (3)0.007 (2)
C80.095 (4)0.037 (3)0.023 (2)0.027 (3)0.015 (2)0.0048 (19)
C90.057 (3)0.072 (4)0.0263 (19)0.023 (3)0.0033 (18)0.015 (2)
C100.041 (2)0.045 (3)0.0253 (19)0.007 (2)0.0037 (17)0.0105 (18)
C110.0244 (17)0.0188 (17)0.0131 (14)0.0019 (13)0.0025 (12)0.0016 (12)
C120.0300 (19)0.0162 (17)0.0155 (15)0.0033 (14)0.0067 (13)0.0017 (13)
C130.0283 (19)0.0253 (19)0.0154 (15)0.0030 (15)0.0000 (13)0.0037 (14)
C140.033 (2)0.028 (2)0.0179 (16)0.0045 (16)0.0009 (14)0.0029 (14)
C150.032 (2)0.0177 (17)0.0251 (17)0.0022 (15)0.0038 (15)0.0023 (14)
C160.0262 (18)0.0167 (17)0.0147 (14)0.0003 (13)0.0023 (13)0.0007 (12)
C170.040 (2)0.0201 (18)0.0175 (16)0.0024 (16)0.0044 (15)0.0042 (14)
C180.049 (3)0.039 (2)0.027 (2)0.010 (2)0.0111 (18)0.0025 (19)
C190.040 (2)0.0143 (19)0.0203 (16)0.0027 (14)0.0040 (14)0.0018 (12)
C200.0226 (16)0.0331 (18)0.0203 (14)0.0020 (18)0.0032 (12)0.0016 (19)
C210.029 (2)0.051 (3)0.0208 (17)0.0104 (18)0.0002 (15)0.0013 (17)
C220.027 (2)0.041 (3)0.068 (3)0.0101 (19)0.004 (2)0.003 (2)
C230.030 (2)0.064 (3)0.031 (2)0.008 (2)0.0078 (17)0.011 (2)
Geometric parameters (Å, º) top
S1—O21.501 (3)C12—C131.402 (5)
S1—N11.652 (3)C12—C171.507 (5)
S1—C201.845 (3)C13—C141.384 (5)
O1—C41.437 (4)C13—H13A0.9500
O1—C21.437 (4)C14—C151.391 (5)
N1—C11.487 (4)C14—C181.518 (5)
N1—H10.82 (4)C15—C161.398 (4)
C1—C111.529 (4)C15—H15A0.9500
C1—C21.554 (5)C16—C191.513 (4)
C1—H1A1.0000C17—H17A0.9800
C2—C31.520 (5)C17—H17B0.9800
C2—H2A1.0000C17—H17C0.9800
C3—H3A0.9800C18—H18A0.9800
C3—H3B0.9800C18—H18B0.9800
C3—H3C0.9800C18—H18C0.9800
C4—C51.515 (5)C19—H19A0.9800
C4—H4A0.9900C19—H19B0.9800
C4—H4B0.9900C19—H19C0.9800
C5—C101.367 (6)C20—C221.511 (6)
C5—C61.391 (6)C20—C211.522 (5)
C6—C71.387 (7)C20—C231.529 (5)
C6—H6A0.9500C21—H21A0.9800
C7—C81.371 (7)C21—H21B0.9800
C7—H7A0.9500C21—H21C0.9800
C8—C91.400 (8)C22—H22A0.9800
C8—H8A0.9500C22—H22B0.9800
C9—C101.406 (7)C22—H22C0.9800
C9—H9A0.9500C23—H23A0.9800
C10—H10A0.9500C23—H23B0.9800
C11—C161.403 (5)C23—H23C0.9800
C11—C121.417 (4)
O2—S1—N1110.67 (15)C14—C13—C12122.0 (3)
O2—S1—C20104.37 (18)C14—C13—H13A119.0
N1—S1—C20103.45 (16)C12—C13—H13A119.0
C4—O1—C2118.0 (3)C13—C14—C15117.9 (3)
C1—N1—S1122.8 (2)C13—C14—C18121.0 (3)
C1—N1—H1113 (3)C15—C14—C18121.1 (4)
S1—N1—H1110 (3)C14—C15—C16122.3 (3)
N1—C1—C11112.3 (3)C14—C15—H15A118.8
N1—C1—C2109.6 (3)C16—C15—H15A118.8
C11—C1—C2113.7 (3)C15—C16—C11119.4 (3)
N1—C1—H1A107.0C15—C16—C19116.9 (3)
C11—C1—H1A107.0C11—C16—C19123.7 (3)
C2—C1—H1A107.0C12—C17—H17A109.5
O1—C2—C3105.7 (3)C12—C17—H17B109.5
O1—C2—C1110.7 (3)H17A—C17—H17B109.5
C3—C2—C1111.7 (3)C12—C17—H17C109.5
O1—C2—H2A109.5H17A—C17—H17C109.5
C3—C2—H2A109.5H17B—C17—H17C109.5
C1—C2—H2A109.5C14—C18—H18A109.5
C2—C3—H3A109.5C14—C18—H18B109.5
C2—C3—H3B109.5H18A—C18—H18B109.5
H3A—C3—H3B109.5C14—C18—H18C109.5
C2—C3—H3C109.5H18A—C18—H18C109.5
H3A—C3—H3C109.5H18B—C18—H18C109.5
H3B—C3—H3C109.5C16—C19—H19A109.5
O1—C4—C5113.6 (3)C16—C19—H19B109.5
O1—C4—H4A108.8H19A—C19—H19B109.5
C5—C4—H4A108.8C16—C19—H19C109.5
O1—C4—H4B108.8H19A—C19—H19C109.5
C5—C4—H4B108.8H19B—C19—H19C109.5
H4A—C4—H4B107.7C22—C20—C21112.0 (3)
C10—C5—C6120.7 (4)C22—C20—C23111.6 (4)
C10—C5—C4121.6 (4)C21—C20—C23109.6 (4)
C6—C5—C4117.7 (4)C22—C20—S1107.2 (3)
C7—C6—C5120.4 (4)C21—C20—S1112.3 (2)
C7—C6—H6A119.8C23—C20—S1103.9 (2)
C5—C6—H6A119.8C20—C21—H21A109.5
C8—C7—C6119.3 (5)C20—C21—H21B109.5
C8—C7—H7A120.4H21A—C21—H21B109.5
C6—C7—H7A120.4C20—C21—H21C109.5
C7—C8—C9120.8 (4)H21A—C21—H21C109.5
C7—C8—H8A119.6H21B—C21—H21C109.5
C9—C8—H8A119.6C20—C22—H22A109.5
C8—C9—C10119.3 (4)C20—C22—H22B109.5
C8—C9—H9A120.3H22A—C22—H22B109.5
C10—C9—H9A120.3C20—C22—H22C109.5
C5—C10—C9119.4 (5)H22A—C22—H22C109.5
C5—C10—H10A120.3H22B—C22—H22C109.5
C9—C10—H10A120.3C20—C23—H23A109.5
C16—C11—C12119.1 (3)C20—C23—H23B109.5
C16—C11—C1122.5 (3)H23A—C23—H23B109.5
C12—C11—C1118.4 (3)C20—C23—H23C109.5
C13—C12—C11119.3 (3)H23A—C23—H23C109.5
C13—C12—C17117.9 (3)H23B—C23—H23C109.5
C11—C12—C17122.8 (3)
O2—S1—N1—C127.5 (3)C2—C1—C11—C1298.0 (4)
C20—S1—N1—C183.8 (3)C16—C11—C12—C131.7 (5)
S1—N1—C1—C11114.3 (3)C1—C11—C12—C13178.9 (3)
S1—N1—C1—C2118.3 (3)C16—C11—C12—C17177.2 (3)
C4—O1—C2—C3146.4 (3)C1—C11—C12—C172.2 (5)
C4—O1—C2—C192.5 (3)C11—C12—C13—C140.1 (5)
N1—C1—C2—O1177.6 (3)C17—C12—C13—C14179.0 (4)
C11—C1—C2—O155.9 (4)C12—C13—C14—C151.3 (6)
N1—C1—C2—C360.1 (3)C12—C13—C14—C18179.8 (4)
C11—C1—C2—C3173.4 (3)C13—C14—C15—C160.7 (6)
C2—O1—C4—C553.4 (4)C18—C14—C15—C16179.2 (4)
O1—C4—C5—C1063.7 (5)C14—C15—C16—C111.2 (5)
O1—C4—C5—C6117.6 (4)C14—C15—C16—C19178.6 (3)
C10—C5—C6—C73.7 (6)C12—C11—C16—C152.3 (5)
C4—C5—C6—C7177.6 (3)C1—C11—C16—C15178.3 (3)
C5—C6—C7—C80.9 (6)C12—C11—C16—C19177.4 (3)
C6—C7—C8—C92.2 (7)C1—C11—C16—C192.0 (5)
C7—C8—C9—C102.6 (6)O2—S1—C20—C22172.3 (3)
C6—C5—C10—C93.3 (5)N1—S1—C20—C2256.5 (3)
C4—C5—C10—C9178.0 (3)O2—S1—C20—C2148.9 (3)
C8—C9—C10—C50.2 (6)N1—S1—C20—C2166.9 (3)
N1—C1—C11—C1643.8 (4)O2—S1—C20—C2369.4 (3)
C2—C1—C11—C1681.3 (4)N1—S1—C20—C23174.7 (3)
N1—C1—C11—C12136.8 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O2i0.83 (4)2.08 (4)2.890 (4)169 (4)
C7—H7A···O1ii0.952.593.501 (6)160
Symmetry codes: (i) x, y+1/2, z+1; (ii) x, y+1, z.
Hydrogen-bond geometry (Å, º) for (1) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O2i0.84 (2)2.23 (2)3.0039 (15)152.8 (7)
C18—H18A···O2i0.982.523.4077 (17)150
C23—H23B···O2i0.982.593.5534 (17)167
Symmetry code: (i) x+1/2, y+1/2, z.
Hydrogen-bond geometry (Å, º) for (2) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O2i0.83 (4)2.08 (4)2.890 (4)169 (4)
C7—H7A···O1ii0.952.593.501 (6)160
Symmetry codes: (i) x, y+1/2, z+1; (ii) x, y+1, z.

Experimental details

(1)(2)
Crystal data
Chemical formulaC22H31NO2SC23H33NO2S
Mr373.54387.56
Crystal system, space groupOrthorhombic, P212121Monoclinic, P21
Temperature (K)100100
a, b, c (Å)9.1567 (13), 10.2951 (15), 22.494 (3)10.535 (3), 7.984 (2), 13.481 (4)
α, β, γ (°)90, 90, 9090, 103.519 (5), 90
V3)2120.5 (5)1102.5 (5)
Z42
Radiation typeMo KαMo Kα
µ (mm1)0.170.16
Crystal size (mm)0.40 × 0.25 × 0.200.50 × 0.14 × 0.10
Data collection
DiffractometerBruker APEXII CCD
diffractometer
Bruker SMART APEXII CCD platform
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2014)
Multi-scan
(SADABS; Bruker, 2014)
Tmin, Tmax0.642, 0.7480.564, 0.746
No. of measured, independent and
observed [I > 2σ(I)] reflections
74315, 11731, 10413 18025, 6191, 4675
Rint0.0410.074
(sin θ/λ)max1)0.8790.695
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.039, 0.096, 1.09 0.055, 0.126, 1.01
No. of reflections117316191
No. of parameters245255
No. of restraints01
H-atom treatmentH atoms treated by a mixture of independent and constrained refinementH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.40, 0.300.72, 0.32
Absolute structureFlack x determined using 4260 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons et al., 2013)Flack x determined using 1713 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons et al., 2013)
Absolute structure parameter0.005 (12)0.03 (6)

Computer programs: APEX2 (Bruker, 2014), SAINT (Bruker, 2014), SHELXS2013 (Sheldrick, 2008), SHELXL2014 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

 

Acknowledgements

The authors thank Keywan Johnson and Kierra Huihui for their expert guidance with the synthetic work and the University of Rochester Chemistry Department (CHM 234) for financial support.

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