rac-2-Phenyl-1-[(2,4,6-triiso­propyl­benzene)­sulfon­yl]aziridine

In the title compound, C₂₃H₃₁NO₂S, the geometry of the triiso­propyl­phenyl group is slightly distorted, with elongated C—C bonds at the ipso-C atom, and an S atom which deviates from the benzene ring plane by 0.228 (2) Å. This distortion is caused by the bulky substituents and, in comparison, an unbent geometry is observed in N-toluene­sulfonyl­aziridine [Zhu et al. (2006). Acta Cryst. E62, o1507–o1508]. π–π inter­actions between adjacent benzene rings [centroid–centroid distance = 3.7928 (11) Å] and are observed.

Key indicators

• Single-crystal X-ray study
• T = 173 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.042
• wR factor = 0.107
• Data-to-parameter ratio = 17.3

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT220_ALERT_2_C Large Non-Solvent    C     Ueq(max)/Ueq(min) ...        3.5 Ratio
PLAT242_ALERT_2_C Low       Ueq as Compared to Neighbors for .....        C16 Check
PLAT906_ALERT_3_C Large K value in the Analysis of Variance ......      2.158 Check

Alert level G
PLAT005_ALERT_5_G No _iucr_refine_instructions_details  in the CIF     Please Do !
PLAT154_ALERT_1_G The su's on the Cell Angles are Equal ..........    0.00400 Deg.
PLAT793_ALERT_4_G The Model has Chirality at C2           (Verify)          S
PLAT910_ALERT_3_G Missing # of FCF Reflections Below Th(Min) .....          3 Why ?

   0 ALERT level A = Most likely a serious problem - resolve or explain
   0 ALERT level B = A potentially serious problem, consider carefully
   3 ALERT level C = Check. Ensure it is not caused by an omission or oversight
   4 ALERT level G = General information/check it is not something unexpected

   1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   2 ALERT type 2 Indicator that the structure model may be wrong or deficient
   2 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion
   1 ALERT type 5 Informative message, check

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S1. Comment

In the past 10 years, interest in aziridinyl anions generated by direct deprotonation grew steadily (Florio & Luisi, 2010). In our group, deprotonation reactions in α- or β-position to amines are a frequent research topic (Gessner & Strohmann, 2007; Gessner & Strohmann, 2008a,b; Unkelbach et al., 2012). We synthesized the compound with the intention to study the deprotonation of the aziridine moiety, which features both the α- and β-position on the same carbon, as well as ringstrain specific effects. The knowledge of the exact structure of the deprotonation substrate is usefull for further discussions of metalleted or substituted derivatives. The succesful deprotonation of such aziridines similar to the title compound were already reported by Huang et al., 2009. The synthesis of the title compound via sulfonium ylide transfer was most recently reportet by Kavanagh et al., 2013.

π—π-Interactions between parallel phenyl groups of adjacent molecules are indicated by a plane-to-plane distance of 3.76 (1) Å, whereas the distance between the isopropyl substituted benzene rings is far longer with 6.30 (1) Å (distance of the centroids). Additionally, interactions between the phenyl ring and the perpendicular aziridine group of an adjacent molecule are possible, with a distance between the ipso-carbon (C9) and the aziridine carbon C1 of 3.43 (1) Å. Thus, a T-shaped π-interaction between the aromat and the aziridin moiety are supposable. The C—C-bonds in the triisopropyl substituted benzene ring are not equidistant, but show slight deviations, similar to those found in other structures containing that group (Sandrock et al., 2004, Laba et al., 2009). Longer C—C-bonds were observed at the ipso-carbon [C9—C10 1.416 (2) Å and C9—C14 1.415 (2) Å] than for the other [C10—C11 1.396 (2) Å, C11—C12 1.385 (2) Å and C12—C13 1.384 (2) Å]. In addition, C—O-distances [C16—O2 2.83 (1) Å and C22—O1 2.98 (1) Å] shorter than the sum of the corresponding van-der-waals radii suggest strong steric repulsion between the isopropyl groups and the sulfonyl oxygen atoms, causing the sulfur atom to bend out of the aromatic plane (defined by C9-C10-C11-C12-C13-C14) of which it deviates by 0.228 (2) Å.

Related literature

For structures containing the triisopropylbenzenesulfonyl group with detailed discussion of the geometry, see: Sandrock et al. (2004); Laba et al. (2009). For the lithiation of activated aziridines, see: Huang et al. (2009) and for a general review on aziridinylanions, see: Florio & Luisi (2010). For the most recent synthesis of the title compound, see: Kavanagh et al. (2013). For deprotonation reactions of aziridinyl anions to amines, see: Gessner & Strohmann (2007, 2008a,b); Unkelbach et al. (2012).

S2. Refinement

All H atoms were placed in calculated positions (aromatic C-H = 0.95 Å, primary C-H = 0.98 Å, secondary C-H = 0.99 Å, tertiary C-H = 1.00 Å) and allowed to ride in the refinement with U_iso(H) = 1.2 U_eq(C) and U_iso(H) = 1.5 U_eq(C) for terminal groups.

Computing details

Data collection: CrysAlis CCD (Oxford Diffraction, 2012); cell refinement: CrysAlis CCD (Oxford Diffraction, 2012); data reduction: CrysAlis RED (Oxford Diffraction, 2012); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2013 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures

	Fig. 1. Molecular structure of the title compound with displacement ellipsoids drawn at 50% probability level.
	Fig. 2. Molecular packing viewed along the a axis with H atoms omitted. Dashed lines indicate π-π-interactions.

rac-2-Phenyl-1-[(2,4,6-triisopropylbenzene)sulfonyl]aziridine

Crystal data

C23H31NO2S	Z = 2
Mr = 385.55	F(000) = 416
Triclinic, P1	Dx = 1.166 Mg m^−3
a = 6.3037 (3) Å	Mo Kα radiation, λ = 0.71073 Å
b = 9.6995 (5) Å	Cell parameters from 5958 reflections
c = 18.6675 (9) Å	θ = 2.7–28.8°
α = 75.280 (4)°	µ = 0.16 mm^−1
β = 86.842 (4)°	T = 173 K
γ = 84.404 (4)°	Needle, colourless
V = 1098.11 (10) Å^3	0.31 × 0.05 × 0.04 mm

Data collection

Agilent Xcalibur Sapphire3 diffractometer	4314 independent reflections
Radiation source: Enhance (Mo) X-ray Source	3633 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.045
Detector resolution: 16.0560 pixels mm^-1	θmax = 26.0°, θmin = 2.3°
φ and ω scans	h = −7→7
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2012)	k = −11→11
Tmin = 0.952, Tmax = 1.000	l = −22→22
17550 measured reflections

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.042	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.107	H-atom parameters constrained
S = 1.06	w = 1/[σ^2(Fo^2) + (0.0409P)^2 + 0.5494P] where P = (Fo^2 + 2Fc^2)/3
4314 reflections	(Δ/σ)max = 0.001
250 parameters	Δρmax = 0.34 e Å^−3
0 restraints	Δρmin = −0.35 e Å^−3
0 constraints

Special details

Experimental. Absorption correction: CrysAlisPro, Agilent Technologies, Version 1.171.36.24 (release 03-12-2012 CrysAlis171 .NET) (compiled Dec 3 2012,18:21:49) Empirical absorption correction using spherical harmonics, implemented in SCALE3 ABSPACK scaling algorithm.

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
S	0.05721 (6)	0.42978 (4)	0.83601 (2)	0.02251 (13)
N	0.2890 (2)	0.41306 (14)	0.87676 (7)	0.0216 (3)
O1	0.01403 (19)	0.28743 (12)	0.83621 (7)	0.0304 (3)
O2	−0.10310 (19)	0.51063 (13)	0.87007 (7)	0.0319 (3)
C1	0.3327 (3)	0.52186 (18)	0.91561 (10)	0.0292 (4)
H1A	0.2270	0.6057	0.9118	0.035*
H1B	0.4829	0.5424	0.9172	0.035*
C2	0.2698 (3)	0.38042 (18)	0.95994 (9)	0.0247 (4)
H2	0.1206	0.3805	0.9811	0.030*
C3	0.4221 (3)	0.26355 (17)	1.00030 (9)	0.0228 (4)
C4	0.6286 (3)	0.24228 (19)	0.97333 (10)	0.0298 (4)
H4	0.6741	0.3024	0.9277	0.036*
C5	0.7692 (3)	0.1342 (2)	1.01235 (11)	0.0349 (4)
H5	0.9114	0.1220	0.9939	0.042*
C6	0.7035 (3)	0.0440 (2)	1.07802 (11)	0.0382 (5)
H6	0.7998	−0.0303	1.1047	0.046*
C7	0.4971 (4)	0.0628 (2)	1.10443 (11)	0.0419 (5)
H7	0.4508	0.0002	1.1492	0.050*
C8	0.3560 (3)	0.1726 (2)	1.06619 (10)	0.0322 (4)
H8	0.2144	0.1853	1.0851	0.039*
C9	0.1211 (3)	0.52378 (17)	0.74302 (9)	0.0205 (3)
C10	0.0207 (3)	0.66079 (17)	0.71038 (9)	0.0238 (4)
C11	0.0609 (3)	0.71662 (18)	0.63479 (9)	0.0282 (4)
H11	−0.0067	0.8077	0.6116	0.034*
C12	0.1947 (3)	0.64572 (19)	0.59189 (9)	0.0286 (4)
C13	0.2961 (3)	0.51463 (18)	0.62672 (9)	0.0272 (4)
H13	0.3914	0.4663	0.5981	0.033*
C14	0.2649 (3)	0.45043 (17)	0.70157 (9)	0.0222 (4)
C15	−0.0578 (5)	0.9059 (2)	0.73340 (15)	0.0609 (7)
H15A	−0.0836	0.9553	0.6815	0.091*
H15B	0.0946	0.9011	0.7426	0.091*
H15C	−0.1392	0.9585	0.7658	0.091*
C16	−0.1279 (3)	0.75541 (18)	0.74931 (10)	0.0309 (4)
H16	−0.1170	0.7129	0.8038	0.037*
C17	−0.3564 (4)	0.7547 (3)	0.73040 (19)	0.0728 (9)
H17A	−0.3732	0.7958	0.6771	0.109*
H17B	−0.4484	0.8118	0.7581	0.109*
H17C	−0.3968	0.6562	0.7436	0.109*
C18	0.3517 (5)	0.8457 (3)	0.49803 (14)	0.0692 (8)
H18A	0.2633	0.9177	0.5174	0.104*
H18B	0.3815	0.8837	0.4450	0.104*
H18C	0.4862	0.8219	0.5241	0.104*
C19	0.2340 (3)	0.7118 (2)	0.50981 (10)	0.0397 (5)
H19	0.3278	0.6407	0.4894	0.048*
C20	0.0285 (4)	0.7429 (3)	0.46754 (13)	0.0653 (7)
H20A	−0.0443	0.6551	0.4762	0.098*
H20B	0.0615	0.7777	0.4144	0.098*
H20C	−0.0642	0.8160	0.4847	0.098*
C21	0.6302 (3)	0.3192 (2)	0.71540 (13)	0.0451 (5)
H21A	0.6587	0.3397	0.6618	0.068*
H21B	0.7101	0.2292	0.7397	0.068*
H21C	0.6746	0.3971	0.7342	0.068*
C22	0.3917 (3)	0.30635 (18)	0.73179 (10)	0.0258 (4)
H22	0.3678	0.2782	0.7868	0.031*
C23	0.3133 (4)	0.1912 (2)	0.69989 (12)	0.0403 (5)
H23A	0.1611	0.1835	0.7123	0.060*
H23B	0.3933	0.0992	0.7209	0.060*
H23C	0.3352	0.2168	0.6459	0.060*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
S	0.0209 (2)	0.0214 (2)	0.0226 (2)	−0.00145 (16)	−0.00392 (16)	−0.00021 (16)
N	0.0227 (7)	0.0221 (7)	0.0195 (7)	−0.0023 (6)	−0.0030 (6)	−0.0038 (5)
O1	0.0315 (7)	0.0229 (6)	0.0347 (7)	−0.0073 (5)	−0.0106 (5)	0.0006 (5)
O2	0.0262 (7)	0.0321 (7)	0.0301 (7)	0.0046 (5)	0.0039 (5)	0.0017 (5)
C1	0.0376 (10)	0.0233 (9)	0.0285 (9)	−0.0014 (8)	−0.0108 (8)	−0.0080 (7)
C2	0.0295 (9)	0.0259 (9)	0.0188 (8)	0.0015 (7)	−0.0014 (7)	−0.0071 (7)
C3	0.0278 (9)	0.0220 (8)	0.0205 (8)	−0.0016 (7)	−0.0050 (7)	−0.0080 (7)
C4	0.0303 (10)	0.0259 (9)	0.0311 (10)	−0.0029 (7)	−0.0014 (8)	−0.0027 (7)
C5	0.0295 (10)	0.0320 (10)	0.0425 (11)	0.0035 (8)	−0.0042 (8)	−0.0094 (8)
C6	0.0482 (13)	0.0290 (10)	0.0352 (11)	0.0106 (9)	−0.0145 (9)	−0.0066 (8)
C7	0.0572 (14)	0.0366 (11)	0.0245 (10)	0.0046 (10)	−0.0016 (9)	0.0027 (8)
C8	0.0372 (11)	0.0354 (10)	0.0223 (9)	0.0011 (8)	0.0012 (8)	−0.0059 (8)
C9	0.0227 (8)	0.0200 (8)	0.0189 (8)	−0.0029 (6)	−0.0058 (6)	−0.0038 (6)
C10	0.0259 (9)	0.0193 (8)	0.0260 (9)	0.0001 (7)	−0.0035 (7)	−0.0056 (7)
C11	0.0333 (10)	0.0205 (8)	0.0265 (9)	0.0056 (7)	−0.0045 (7)	−0.0003 (7)
C12	0.0339 (10)	0.0282 (9)	0.0219 (9)	0.0017 (8)	−0.0053 (7)	−0.0038 (7)
C13	0.0293 (9)	0.0276 (9)	0.0253 (9)	0.0053 (7)	−0.0040 (7)	−0.0097 (7)
C14	0.0230 (9)	0.0201 (8)	0.0247 (8)	−0.0001 (7)	−0.0083 (7)	−0.0065 (7)
C15	0.0812 (19)	0.0319 (12)	0.0736 (17)	−0.0089 (12)	0.0258 (14)	−0.0251 (12)
C16	0.0393 (11)	0.0205 (9)	0.0295 (9)	0.0048 (8)	0.0035 (8)	−0.0037 (7)
C17	0.0355 (13)	0.084 (2)	0.117 (3)	0.0111 (13)	−0.0003 (14)	−0.0659 (19)
C18	0.087 (2)	0.0712 (18)	0.0413 (14)	−0.0245 (15)	0.0178 (13)	0.0033 (12)
C19	0.0517 (13)	0.0381 (11)	0.0227 (9)	0.0129 (9)	0.0010 (9)	−0.0022 (8)
C20	0.0744 (18)	0.0837 (19)	0.0292 (12)	0.0079 (15)	−0.0155 (12)	−0.0012 (12)
C21	0.0329 (11)	0.0404 (12)	0.0580 (14)	0.0097 (9)	−0.0171 (10)	−0.0066 (10)
C22	0.0306 (9)	0.0219 (9)	0.0253 (9)	0.0054 (7)	−0.0095 (7)	−0.0073 (7)
C23	0.0517 (13)	0.0244 (10)	0.0470 (12)	0.0056 (9)	−0.0197 (10)	−0.0126 (9)

Geometric parameters (Å, º)

S—O1	1.4322 (12)	C13—C14	1.389 (2)
S—O2	1.4382 (13)	C13—H13	0.9500
S—N	1.6597 (14)	C14—C22	1.530 (2)
S—C9	1.7880 (16)	C15—C16	1.518 (3)
N—C1	1.478 (2)	C15—H15A	0.9800
N—C2	1.504 (2)	C15—H15B	0.9800
C1—C2	1.489 (2)	C15—H15C	0.9800
C1—H1A	0.9900	C16—C17	1.503 (3)
C1—H1B	0.9900	C16—H16	1.0000
C2—C3	1.486 (2)	C17—H17A	0.9800
C2—H2	1.0000	C17—H17B	0.9800
C3—C4	1.385 (2)	C17—H17C	0.9800
C3—C8	1.389 (2)	C18—C19	1.519 (3)
C4—C5	1.384 (3)	C18—H18A	0.9800
C4—H4	0.9500	C18—H18B	0.9800
C5—C6	1.382 (3)	C18—H18C	0.9800
C5—H5	0.9500	C19—C20	1.519 (3)
C6—C7	1.378 (3)	C19—H19	1.0000
C6—H6	0.9500	C20—H20A	0.9800
C7—C8	1.390 (3)	C20—H20B	0.9800
C7—H7	0.9500	C20—H20C	0.9800
C8—H8	0.9500	C21—C22	1.528 (3)
C9—C14	1.415 (2)	C21—H21A	0.9800
C9—C10	1.416 (2)	C21—H21B	0.9800
C10—C11	1.396 (2)	C21—H21C	0.9800
C10—C16	1.531 (2)	C22—C23	1.525 (2)
C11—C12	1.385 (2)	C22—H22	1.0000
C11—H11	0.9500	C23—H23A	0.9800
C12—C13	1.384 (2)	C23—H23B	0.9800
C12—C19	1.520 (2)	C23—H23C	0.9800
O1—S—O2	116.59 (8)	C9—C14—C22	125.91 (15)
O1—S—N	105.66 (7)	C16—C15—H15A	109.5
O2—S—N	111.07 (7)	C16—C15—H15B	109.5
O1—S—C9	108.62 (7)	H15A—C15—H15B	109.5
O2—S—C9	111.50 (7)	C16—C15—H15C	109.5
N—S—C9	102.29 (7)	H15A—C15—H15C	109.5
C1—N—C2	59.91 (11)	H15B—C15—H15C	109.5
C1—N—S	118.58 (11)	C17—C16—C15	112.2 (2)
C2—N—S	113.79 (11)	C17—C16—C10	111.28 (16)
N—C1—C2	60.94 (10)	C15—C16—C10	111.45 (16)
N—C1—H1A	117.7	C17—C16—H16	107.2
C2—C1—H1A	117.7	C15—C16—H16	107.2
N—C1—H1B	117.7	C10—C16—H16	107.2
C2—C1—H1B	117.7	C16—C17—H17A	109.5
H1A—C1—H1B	114.8	C16—C17—H17B	109.5
C3—C2—C1	124.07 (16)	H17A—C17—H17B	109.5
C3—C2—N	115.58 (13)	C16—C17—H17C	109.5
C1—C2—N	59.15 (10)	H17A—C17—H17C	109.5
C3—C2—H2	115.3	H17B—C17—H17C	109.5
C1—C2—H2	115.3	C19—C18—H18A	109.5
N—C2—H2	115.3	C19—C18—H18B	109.5
C4—C3—C8	119.08 (16)	H18A—C18—H18B	109.5
C4—C3—C2	121.46 (15)	C19—C18—H18C	109.5
C8—C3—C2	119.45 (16)	H18A—C18—H18C	109.5
C5—C4—C3	120.59 (17)	H18B—C18—H18C	109.5
C5—C4—H4	119.7	C20—C19—C18	111.1 (2)
C3—C4—H4	119.7	C20—C19—C12	111.87 (18)
C6—C5—C4	120.28 (18)	C18—C19—C12	110.91 (17)
C6—C5—H5	119.9	C20—C19—H19	107.6
C4—C5—H5	119.9	C18—C19—H19	107.6
C7—C6—C5	119.43 (18)	C12—C19—H19	107.6
C7—C6—H6	120.3	C19—C20—H20A	109.5
C5—C6—H6	120.3	C19—C20—H20B	109.5
C6—C7—C8	120.63 (18)	H20A—C20—H20B	109.5
C6—C7—H7	119.7	C19—C20—H20C	109.5
C8—C7—H7	119.7	H20A—C20—H20C	109.5
C3—C8—C7	119.96 (18)	H20B—C20—H20C	109.5
C3—C8—H8	120.0	C22—C21—H21A	109.5
C7—C8—H8	120.0	C22—C21—H21B	109.5
C14—C9—C10	121.29 (15)	H21A—C21—H21B	109.5
C14—C9—S	116.84 (12)	C22—C21—H21C	109.5
C10—C9—S	121.69 (12)	H21A—C21—H21C	109.5
C11—C10—C9	117.04 (15)	H21B—C21—H21C	109.5
C11—C10—C16	116.07 (14)	C23—C22—C21	111.22 (16)
C9—C10—C16	126.88 (15)	C23—C22—C14	110.57 (14)
C12—C11—C10	123.22 (15)	C21—C22—C14	110.51 (15)
C12—C11—H11	118.4	C23—C22—H22	108.1
C10—C11—H11	118.4	C21—C22—H22	108.1
C13—C12—C11	117.74 (16)	C14—C22—H22	108.1
C13—C12—C19	121.16 (16)	C22—C23—H23A	109.5
C11—C12—C19	121.07 (16)	C22—C23—H23B	109.5
C12—C13—C14	123.04 (16)	H23A—C23—H23B	109.5
C12—C13—H13	118.5	C22—C23—H23C	109.5
C14—C13—H13	118.5	H23A—C23—H23C	109.5
C13—C14—C9	117.56 (15)	H23B—C23—H23C	109.5
C13—C14—C22	116.53 (15)