organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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4,4′-Di­methyl-2,2′-{[2,3,3a,4,5,6,7,7a-octa­hydro-1H-benzimidazole-1,3-di­yl]bis­­(methyl­ene)}diphenol

aUniversidad Nacional de Colombia, Sede Bogotá, Facultad de Ciencias, Departamento de Química, Cra 30 No. 45-03, Bogotá, Código Postal 111321, Colombia, bUniversidad Nacional de Colombia, Sede Manizales, Colombia, and cInstitut für Anorganische Chemie, J. W. Goethe-Universität Frankfurt, Max-von-Laue-Str. 7, 60438 Frankfurt/Main, Germany
*Correspondence e-mail: ariverau@unal.edu.co

(Received 28 May 2013; accepted 1 June 2013; online 8 June 2013)

The asymmetric unit of the title compound, C23H30N2O2, contains one half-mol­ecule, with a twofold axis splitting the mol­ecule in two identical halves. The structure of the racemic mixture has been reported previously [Rivera et al. (2009[Rivera, A., Quiroga, D., Rios-Motta, J., Carda, J. & Peris, G. (2009). J. Chem. Crystallogr. 39, 827-830.]) J. Chem. Crystallogr. 39, 827–830] but the enanti­omer reported here crystallized in the ortho­rhom­bic space group P21212 (Z = 2), whereas the racemate occurs in the triclinic space group P-1 (Z = 2). The observed mol­ecular conformation is stabilized by two intra­molecular O—H⋯N hydrogen bonds, which generate rings with graph-set motif S(6). In the crystal, mol­ecules are linked via non-classical C—H⋯O inter­actions, which stack the mol­ecules along the b axis.

Related literature

For the structure of the original racemate, see: Rivera et al. (2009[Rivera, A., Quiroga, D., Rios-Motta, J., Carda, J. & Peris, G. (2009). J. Chem. Crystallogr. 39, 827-830.]). For the use of 1,3-di­aza­heterocyclic-bridged bis­(phenols) in coordination chemistry, see: Kober et al. (2012[Kober, E., Nerkowski, T., Janas, Z. & Jerzykiewicz, L. B. (2012). Dalton Trans. 41, 5188-5192.]); Xu et al. (2007[Xu, X., Yao, Y., Zhang, Y. & Shen, Q. (2007). Inorg. Chem. 46, 3743-3751.]). For the synthesis of the precursor, (2R,7R)- 1,8,10,12-tetra­aza­tetra­cyclo­[8.3.118,12.02,7]penta­decane, see: Rivera et al. (2012[Rivera, A., Quiroga, D., Jiménez-Cruz, L., Fejfarová, K. & Dusek, M. (2012). Tetrahedron Lett. 53, 345-348.]). For bond-length data, see: Allen et al. (1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]). For graph-set analysis, see: Bernstein et al. (1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]).

[Scheme 1]

Experimental

Crystal data
  • C23H30N2O2

  • Mr = 366.49

  • Orthorhombic, P 21 21 2

  • a = 18.5417 (9) Å

  • b = 6.0597 (4) Å

  • c = 8.9415 (5) Å

  • V = 1004.64 (10) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.08 mm−1

  • T = 173 K

  • 0.31 × 0.27 × 0.12 mm

Data collection
  • STOE IPDS II two-circle-diffractometer

  • Absorption correction: multi-scan (X-AREA; Stoe & Cie, 2001[Stoe & Cie (2001). X-AREA and X-RED32. Stoe & Cie, Darmstadt, Germany.]) Tmin = 0.976, Tmax = 0.991

  • 12723 measured reflections

  • 2168 independent reflections

  • 2058 reflections with I > 2σ(I)

  • Rint = 0.053

Refinement
  • R[F2 > 2σ(F2)] = 0.034

  • wR(F2) = 0.090

  • S = 1.04

  • 2168 reflections

  • 129 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.14 e Å−3

  • Δρmin = −0.13 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O1—H1⋯N1 1.03 (4) 1.73 (4) 2.667 (2) 150 (3)
C4—H4⋯O1i 0.99 2.63 3.3749 (13) 133
C5—H5B⋯O1ii 0.99 2.63 3.522 (2) 150
Symmetry codes: (i) -x+1, -y+1, z; (ii) x, y-1, z.

Data collection: X-AREA (Stoe & Cie, 2001[Stoe & Cie (2001). X-AREA and X-RED32. Stoe & Cie, Darmstadt, Germany.]); cell refinement: X-AREA; data reduction: X-RED32 (Stoe & Cie, 2001[Stoe & Cie (2001). X-AREA and X-RED32. Stoe & Cie, Darmstadt, Germany.]); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL2012 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: XP in SHELXTL-Plus (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXL2012.

Supporting information


Comment top

Chiral 1,3-diazaheterocyclic-bridged bis(phenols) form stable complexes with several metals and are of interest as ligands to metal complexes because they produce asymmetric coordination compounds (Xu et al., 2007; Kober et al., 2012) and therefore may be involved in enantioselective catalysis.

The title compound (I) was synthesized in a one-step reaction between the chiral macrocyclic aminal (2R,7R)-1,8,10,12-tetraazatetracyclo[8.3.118,12.02,7]pentadecane and p-cresol. Single crystals of were obtained by recrystallization from CHCl3 solution.

The molecular structure and atom-numbering scheme for (I) are shown in Fig. 1. The bond lengths and angles are within normal ranges (Allen et al., 1987) and are comparable with those reported previously reported racemate (Rivera et al., 2009). The space group, of the title enantiomer, P21212, differs from that of the racemate which was triclinic, P-1. (Rivera et al., 2009).

The crystal structure of (I) shows two intramolecular hydrogen bonds generating rings with graph-set motif S(6) (Bernstein et al., 1995) (Table 1). In the crystal, molecules are linked via non-classical intermolecular C—H···O interactions, which stack the molecules along the b axis.

Related literature top

For the structure of the original racemate, see: Rivera et al. (2009). For the use of 1,3-diazaheterocyclic-bridged bis(phenols) in coordination chemistry, see: Kober et al. (2012); Xu et al. (2007). For the synthesis of the precursor, (2R,7R)- 1,8,10,12-tetraazatetracyclo[8.3.118,12.02,7]pentadecane, see: Rivera et al. (2012). For bond-length data, see: Allen et al. (1987). For graph-set analysis, see: Bernstein et al. (1995).

Experimental top

The title compound was synthesized according to the published procedure (Rivera et al., 2012) by reacting (2R,7R)-1,8,10,12-tetraazatetracyclo [8.3.118,12.02,7]pentadecane (1 mmol, [α]20D -25.1, c = O.6% CH2Cl2) and p-cresol (1 mmol). After work-up a solid was obtained by slow evaporation from chloroform at room temperature. After standing for two days, crystals suitable for X-ray diffraction were grown from a solution in CHCl3 obtained in 37% yield, m.p. = 464 K, [α]20D -54.4, c = O.6 in CHCl3.

Refinement top

The hydroxyl H atom was freely refined. H atoms bound to carbon were refined using a riding model with methyl C—H = 0.98 Å, aromatic C—H = 0.95 Å, secondary C—H = 0.99 Å, and with Uiso(H) = 1.5Ueq(C) for methyl H or 1.2Ueq(C) for aromatic and secondary H.

_reflns_Friedel_fraction is defined as the number of unique Friedel pairs measured divided by the number that would be possible theoretically, ignoring centric projections and systematic absences

Structure description top

Chiral 1,3-diazaheterocyclic-bridged bis(phenols) form stable complexes with several metals and are of interest as ligands to metal complexes because they produce asymmetric coordination compounds (Xu et al., 2007; Kober et al., 2012) and therefore may be involved in enantioselective catalysis.

The title compound (I) was synthesized in a one-step reaction between the chiral macrocyclic aminal (2R,7R)-1,8,10,12-tetraazatetracyclo[8.3.118,12.02,7]pentadecane and p-cresol. Single crystals of were obtained by recrystallization from CHCl3 solution.

The molecular structure and atom-numbering scheme for (I) are shown in Fig. 1. The bond lengths and angles are within normal ranges (Allen et al., 1987) and are comparable with those reported previously reported racemate (Rivera et al., 2009). The space group, of the title enantiomer, P21212, differs from that of the racemate which was triclinic, P-1. (Rivera et al., 2009).

The crystal structure of (I) shows two intramolecular hydrogen bonds generating rings with graph-set motif S(6) (Bernstein et al., 1995) (Table 1). In the crystal, molecules are linked via non-classical intermolecular C—H···O interactions, which stack the molecules along the b axis.

For the structure of the original racemate, see: Rivera et al. (2009). For the use of 1,3-diazaheterocyclic-bridged bis(phenols) in coordination chemistry, see: Kober et al. (2012); Xu et al. (2007). For the synthesis of the precursor, (2R,7R)- 1,8,10,12-tetraazatetracyclo[8.3.118,12.02,7]pentadecane, see: Rivera et al. (2012). For bond-length data, see: Allen et al. (1987). For graph-set analysis, see: Bernstein et al. (1995).

Computing details top

Data collection: X-AREA (Stoe & Cie, 2001); cell refinement: X-AREA (Stoe & Cie, 2001); data reduction: X-RED32 (Stoe & Cie, 2001); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2012 (Sheldrick, 2008); molecular graphics: XP in SHELXTL-Plus (Sheldrick, 2008); software used to prepare material for publication: SHELXL2012 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. A perspective view of the title compound. Displacement ellipsoids are drawn at the 50% probability level and H atoms are shown as small spheres with arbitrary radii. Intramolecular hydrogen bonds are drawn as dashed lines.
4,4'-Dimethyl-2,2'-{[2,3,3a,4,5,6,7,7a-octahydro-1H-benzimidazole-1,3-diyl]bis(methylene)}diphenol top
Crystal data top
C23H30N2O2Dx = 1.212 Mg m3
Mr = 366.49Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, P21212Cell parameters from 16515 reflections
a = 18.5417 (9) Åθ = 2.2–27.5°
b = 6.0597 (4) ŵ = 0.08 mm1
c = 8.9415 (5) ÅT = 173 K
V = 1004.64 (10) Å3Plate, colourless
Z = 20.31 × 0.27 × 0.12 mm
F(000) = 396
Data collection top
STOE IPDS II two-circle-
diffractometer
2058 reflections with I > 2σ(I)
Radiation source: Genix 3D IµS microfocus X-ray sourceRint = 0.053
ω scansθmax = 26.9°, θmin = 2.2°
Absorption correction: multi-scan
(X-AREA; Stoe & Cie, 2001)
h = 2323
Tmin = 0.976, Tmax = 0.991k = 77
12723 measured reflectionsl = 1111
2168 independent reflections
Refinement top
Refinement on F2Hydrogen site location: mixed
Least-squares matrix: fullH atoms treated by a mixture of independent and constrained refinement
R[F2 > 2σ(F2)] = 0.034 w = 1/[σ2(Fo2) + (0.0482P)2 + 0.1419P]
where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.090(Δ/σ)max < 0.001
S = 1.04Δρmax = 0.14 e Å3
2168 reflectionsΔρmin = 0.13 e Å3
129 parametersExtinction correction: SHELXL, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
0 restraintsExtinction coefficient: 0.075 (11)
Crystal data top
C23H30N2O2V = 1004.64 (10) Å3
Mr = 366.49Z = 2
Orthorhombic, P21212Mo Kα radiation
a = 18.5417 (9) ŵ = 0.08 mm1
b = 6.0597 (4) ÅT = 173 K
c = 8.9415 (5) Å0.31 × 0.27 × 0.12 mm
Data collection top
STOE IPDS II two-circle-
diffractometer
2168 independent reflections
Absorption correction: multi-scan
(X-AREA; Stoe & Cie, 2001)
2058 reflections with I > 2σ(I)
Tmin = 0.976, Tmax = 0.991Rint = 0.053
12723 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0340 restraints
wR(F2) = 0.090H atoms treated by a mixture of independent and constrained refinement
S = 1.04Δρmax = 0.14 e Å3
2168 reflectionsΔρmin = 0.13 e Å3
129 parameters
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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
O10.41870 (7)0.5018 (2)0.60166 (17)0.0414 (3)
H10.4384 (19)0.376 (6)0.668 (4)0.097 (11)*
N10.44460 (7)0.0979 (2)0.70721 (16)0.0303 (3)
C10.45928 (9)0.0063 (3)0.85614 (19)0.0340 (4)
H1A0.43930.14680.86110.041*
C20.43253 (11)0.1352 (4)0.9905 (2)0.0477 (5)
H2A0.37920.14140.99010.057*
H2B0.45130.28800.98730.057*
C30.45917 (12)0.0182 (5)1.1318 (2)0.0596 (7)
H3A0.44580.10741.22040.071*
H3B0.43470.12641.14050.071*
C40.50000.00000.6072 (3)0.0305 (5)
H40.52170.11500.54270.037*
C50.36990 (9)0.0576 (3)0.6571 (2)0.0332 (4)
H5A0.33620.10070.73780.040*
H5B0.36340.10210.63800.040*
C110.35166 (9)0.1843 (3)0.5173 (2)0.0301 (4)
C120.37743 (9)0.3996 (3)0.4958 (2)0.0330 (4)
C130.35991 (10)0.5134 (3)0.3660 (2)0.0389 (4)
H130.37880.65710.34960.047*
C140.31501 (10)0.4180 (4)0.2604 (2)0.0389 (4)
H140.30320.49830.17240.047*
C150.28681 (10)0.2075 (3)0.2801 (2)0.0359 (4)
C160.30625 (9)0.0935 (3)0.4097 (2)0.0320 (4)
H160.28780.05110.42490.038*
C170.23790 (11)0.1007 (4)0.1658 (2)0.0452 (5)
H17A0.22780.20600.08520.068*
H17B0.19260.05710.21380.068*
H17C0.26170.03000.12410.068*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0387 (7)0.0295 (6)0.0559 (8)0.0030 (6)0.0083 (6)0.0022 (7)
N10.0243 (7)0.0345 (7)0.0319 (7)0.0019 (6)0.0008 (5)0.0008 (6)
C10.0298 (9)0.0385 (8)0.0337 (9)0.0043 (7)0.0003 (6)0.0036 (8)
C20.0383 (10)0.0677 (14)0.0371 (10)0.0140 (10)0.0033 (9)0.0034 (10)
C30.0501 (13)0.0951 (19)0.0335 (10)0.0207 (13)0.0048 (9)0.0018 (12)
C40.0262 (10)0.0315 (11)0.0339 (11)0.0007 (9)0.0000.000
C50.0251 (8)0.0346 (8)0.0398 (9)0.0014 (7)0.0005 (7)0.0043 (7)
C110.0238 (7)0.0296 (8)0.0369 (9)0.0024 (6)0.0013 (7)0.0006 (7)
C120.0274 (8)0.0301 (8)0.0414 (9)0.0012 (7)0.0003 (7)0.0015 (8)
C130.0371 (9)0.0316 (8)0.0482 (10)0.0008 (7)0.0058 (8)0.0062 (8)
C140.0377 (9)0.0410 (10)0.0380 (9)0.0077 (8)0.0028 (8)0.0062 (8)
C150.0305 (8)0.0409 (10)0.0363 (9)0.0048 (7)0.0014 (8)0.0021 (8)
C160.0270 (8)0.0303 (8)0.0388 (9)0.0001 (7)0.0020 (7)0.0013 (7)
C170.0427 (10)0.0546 (11)0.0384 (10)0.0024 (9)0.0037 (8)0.0041 (10)
Geometric parameters (Å, º) top
O1—C121.365 (2)C5—C111.505 (2)
O1—H11.03 (4)C5—H5A0.9900
N1—C11.468 (2)C5—H5B0.9900
N1—C51.476 (2)C11—C161.392 (3)
N1—C41.485 (2)C11—C121.403 (2)
C1—C1i1.512 (3)C12—C131.389 (3)
C1—C21.516 (3)C13—C141.386 (3)
C1—H1A1.0000C13—H130.9500
C2—C31.531 (3)C14—C151.390 (3)
C2—H2A0.9900C14—H140.9500
C2—H2B0.9900C15—C161.396 (3)
C3—C3i1.530 (4)C15—C171.512 (3)
C3—H3A0.9900C16—H160.9500
C3—H3B0.9900C17—H17A0.9800
C4—N1i1.485 (2)C17—H17B0.9800
C4—H40.9900C17—H17C0.9800
C12—O1—H1105 (2)N1—C5—H5B109.2
C1—N1—C5112.75 (14)C11—C5—H5B109.2
C1—N1—C4105.47 (13)H5A—C5—H5B107.9
C5—N1—C4113.58 (14)C16—C11—C12118.61 (17)
N1—C1—C1i101.79 (11)C16—C11—C5120.55 (15)
N1—C1—C2117.60 (15)C12—C11—C5120.78 (16)
C1i—C1—C2110.66 (14)O1—C12—C13119.01 (16)
N1—C1—H1A108.8O1—C12—C11121.19 (17)
C1i—C1—H1A108.8C13—C12—C11119.79 (17)
C2—C1—H1A108.8C14—C13—C12120.22 (17)
C1—C2—C3108.07 (17)C14—C13—H13119.9
C1—C2—H2A110.1C12—C13—H13119.9
C3—C2—H2A110.1C13—C14—C15121.48 (18)
C1—C2—H2B110.1C13—C14—H14119.3
C3—C2—H2B110.1C15—C14—H14119.3
H2A—C2—H2B108.4C14—C15—C16117.54 (18)
C3i—C3—C2112.71 (18)C14—C15—C17122.16 (19)
C3i—C3—H3A109.0C16—C15—C17120.28 (18)
C2—C3—H3A109.0C11—C16—C15122.30 (17)
C3i—C3—H3B109.0C11—C16—H16118.8
C2—C3—H3B109.0C15—C16—H16118.8
H3A—C3—H3B107.8C15—C17—H17A109.5
N1i—C4—N1106.00 (19)C15—C17—H17B109.5
N1i—C4—H4110.5H17A—C17—H17B109.5
N1—C4—H4110.5C15—C17—H17C109.5
N1—C5—C11112.24 (14)H17A—C17—H17C109.5
N1—C5—H5A109.2H17B—C17—H17C109.5
C11—C5—H5A109.2
C5—N1—C1—C1i160.26 (17)C16—C11—C12—O1176.16 (15)
C4—N1—C1—C1i35.78 (19)C5—C11—C12—O11.1 (2)
C5—N1—C1—C278.7 (2)C16—C11—C12—C132.7 (2)
C4—N1—C1—C2156.83 (15)C5—C11—C12—C13180.00 (15)
N1—C1—C2—C3175.55 (19)O1—C12—C13—C14176.61 (17)
C1i—C1—C2—C359.2 (2)C11—C12—C13—C142.3 (3)
C1—C2—C3—C3i53.8 (3)C12—C13—C14—C150.4 (3)
C1—N1—C4—N1i14.09 (8)C13—C14—C15—C160.9 (3)
C5—N1—C4—N1i138.05 (15)C13—C14—C15—C17179.83 (18)
C1—N1—C5—C11170.22 (14)C12—C11—C16—C151.4 (3)
C4—N1—C5—C1169.88 (17)C5—C11—C16—C15178.62 (16)
N1—C5—C11—C16144.70 (16)C14—C15—C16—C110.5 (3)
N1—C5—C11—C1238.1 (2)C17—C15—C16—C11179.38 (17)
Symmetry code: (i) x+1, y, z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1···N11.03 (4)1.73 (4)2.667 (2)150 (3)
C4—H4···O1ii0.992.633.3749 (13)133
C5—H5B···O1iii0.992.633.522 (2)150
Symmetry codes: (ii) x+1, y+1, z; (iii) x, y1, z.

Experimental details

Crystal data
Chemical formulaC23H30N2O2
Mr366.49
Crystal system, space groupOrthorhombic, P21212
Temperature (K)173
a, b, c (Å)18.5417 (9), 6.0597 (4), 8.9415 (5)
V3)1004.64 (10)
Z2
Radiation typeMo Kα
µ (mm1)0.08
Crystal size (mm)0.31 × 0.27 × 0.12
Data collection
DiffractometerSTOE IPDS II two-circle-
diffractometer
Absorption correctionMulti-scan
(X-AREA; Stoe & Cie, 2001)
Tmin, Tmax0.976, 0.991
No. of measured, independent and
observed [I > 2σ(I)] reflections
12723, 2168, 2058
Rint0.053
(sin θ/λ)max1)0.636
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.034, 0.090, 1.04
No. of reflections2168
No. of parameters129
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.14, 0.13

Computer programs: X-AREA (Stoe & Cie, 2001), X-RED32 (Stoe & Cie, 2001), SHELXS97 (Sheldrick, 2008), SHELXL2012 (Sheldrick, 2008), XP in SHELXTL-Plus (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1···N11.03 (4)1.73 (4)2.667 (2)150 (3)
C4—H4···O1i0.992.633.3749 (13)132.6
C5—H5B···O1ii0.992.633.522 (2)150.0
Symmetry codes: (i) x+1, y+1, z; (ii) x, y1, z.
 

Acknowledgements

We acknowledge the Dirección de Investigaciones, Sede Bogotá (DIB) y Sede Manizales (DIMA) de la Universidad Nacional de Colombia, for financial support of this work

References

First citationAllen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1–19.  CSD CrossRef Web of Science Google Scholar
First citationBernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555–1573.  CrossRef CAS Web of Science Google Scholar
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