A 1:1 molecular complex of 4-amino­cyclo­hexanol and (4-hydroxy­cyclo­hexyl)­carbamic acid

Dey, A.; Desiraju, G.R.; Mondal, R.; Howard, J.A.K.

doi:10.1107/S1600536804009134

organic compounds

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 60| Part 5| May 2004| Pages o857-o859

https://doi.org/10.1107/S1600536804009134

A 1:1 molecular complex of 4-aminocyclohexanol and (4-hydroxycyclohexyl)carbamic acid

Archan Dey,^a Gautam R. Desiraju,^a ^* Raju Mondal ^b and Judith A. K. Howard ^b

^aSchool of Chemistry, University of Hyderabad, Hyderabad 500 046, India, and ^bDepartment of Chemistry, University of Durham, Durham DH1 3LE, England
^*Correspondence e-mail: desiraju@uohyd.ernet.in

(Received 9 March 2004; accepted 16 April 2004; online 24 April 2004)

The title molecular complex, 4-ammoniocyclohexanol (4-hydroxycyclohexyl)carbamate, C₆H₁₄NO⁺·C₇H₁₂NO₃⁻, forms an ionic column with N—H⋯O, O—H⋯O and C—H⋯O interactions. There are two different cyclic supramolecular synthons of note. The crystal structures of ionic amino acids also have similar structural patterns.

Comment

The title molecular complex, (I), was obtained during a study of 4-aminocyclohexanol. This type of compound has a tendency to form carbonated adducts by reaction with atmospheric CO₂. In this regard, the crystal structure of 2-aminocyclohexylcarbamate has been reported (Hanessian et al., 1995 ). In our case, 4-hydroxycyclohexylcarbamic acid initially formed, then crystallized with the original 4-aminocyclohexanol to give a 1:1 ionic molecular complex with proton transfer.

The molecular structure and atom numbering are given in Fig. 1. The main features are similar to those in the molecular complex of methyl 3-acetoxy-1-ammonio-4-iodocyclohexane-1-carboxylate and trifluoroacetate (Avenoza et al., 1997 ) and similar to 2-aminocyclohexylcarbamate (Hanessian et al., 1995). The ions form a columnar arrangement with several N—H⋯O interactions (Table 1); the packing is shown in Fig. 2. Weak C—H⋯O interactions (Table 1) reinforce the column formation. A closer view of the columnar packing shows that it is composed of two cyclic supramolecular synthons A and B (Fig. 3). Both types of synthon are observed in other ionic amino acids. In the Cambridge Structural Database (Version 5.24, July 2003; Allen, 2002 ), the crystal structures with refcodes ACXTPY (Bhattacharjee et al., 1975 ), ACYHXA01 (Valle et al., 1988 ), DMTYRS (Gaudestad et al., 1976 ), FOBJUB (Pirrung, 1987 ), MEMTYR10 (Satyshur & Rao, 1983 ) RIGSEF (Avenoza et al., 1997) and TOKNUC (Allan et al., 1996 ) contain synthons A and B.

O—H⋯O(carboxylate) and O—H⋯O(hydroxyl) hydrogen bonds act as connectors between the columns.

Figure 1
A view of the molecular structure of the title complex, with the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level and H atoms are shown as small spheres of arbitrary radii.

Figure 2
Stereoview of the columnar packing, viewed down the a axis. Hydrogen bonds are shown as dashed lines.

Figure 3
Segment of the crystal structure, showing synthons A and B.

Experimental

Neutralization of the commercially available (Lancaster) hydrochloride salt of 4-aminocyclohexanol by NaHCO₃ in water affords the 4-aminocyclohexanol (extracted with EtOAc). The compound crystallized from a 1:1:1 mixture of EtOAc, CH₃CN and EtOH. During the time of crystallization, 4-aminocyclohexanol is carboxylated by atmospheric CO₂ to give the carbamic acid which cocrystallizes with the parent compound to give yellow crystals of the 1:1 molecular complex.

Crystal data

C₆H₁₄NO⁺·C₇H₁₂NO₃⁻
M_r = 274.36
Monoclinic, P2₁/c
a = 6.3452 (2) Å
b = 18.6256 (6) Å
c = 12.1664 (4) Å
β = 92.284 (2)°
V = 1436.72 (8) Å³
Z = 4
D_x = 1.268 Mg m⁻³
Mo Kα radiation
Cell parameters from 4934 reflections
θ = 2.8–27.5°
μ = 0.09 mm⁻¹
T = 120 (2) K
Plate, yellow
0.22 × 0.12 × 0.04 mm

Data collection

SMART 6K CCD area-detector diffractometer
ω scans
Absorption correction: multi-scan (SADABS; Bruker, 2001 ) T_min = 0.927, T_max = 1.000
19783 measured reflections
3308 independent reflections
2537 reflections with I > 2σ(I)
R_int = 0.038
θ_max = 27.5°
h = −7 → 8
k = −24 → 24
l = −15 → 15

Refinement

Refinement on F²
R[F² > 2σ(F²)] = 0.037
wR(F²) = 0.102
S = 1.01
3308 reflections
276 parameters
All H-atom parameters refined
w = 1/[σ²(F_o²) + (0.0538P)² + 0.3252P] where P = (F_o² + 2F_c²)/3
(Δ/σ)_max = 0.001
Δρ_max = 0.27 e Å⁻³
Δρ_min = −0.18 e Å⁻³

Table 1
Hydrogen-bonding geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1′—H1′⋯O1	0.90 (2)	1.88 (2)	2.784 (2)	176 (1)
O1—H1⋯O3ⁱ	0.90 (2)	1.79 (2)	2.687 (1)	175 (2)
N1′—H111⋯O2ⁱⁱ	0.94 (2)	1.90 (2)	2.816 (1)	167 (1)
N1′—H112⋯O3ⁱⁱⁱ	0.95 (2)	1.82 (2)	2.7590 (1)	170 (1)
N1′—H114⋯O2^iv	0.92 (2)	1.87 (2)	2.7870 (1)	169 (1)
C6′—H6D⋯O3ⁱⁱ	0.96 (2)	2.54 (1)	3.417 (1)	152 (1)
Symmetry codes: (i) $[1+x,{\script{3\over 2}}-y,{\script{1\over 2}}+z]$ ; (ii) 1+x,y,1+z; (iii) -x,1-y,1-z; (iv) 1-x,1-y,1-z.

Data collection: SMART (Bruker, 1997 ); cell refinement: SMART; data reduction: SAINT (Bruker, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 2001); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S1600536804009134/fl6095sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536804009134/fl6095Isup2.hkl

Computing details top

Data collection: SMART (Bruker, 1997); cell refinement: SMART; data reduction: SAINT (Bruker, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 2001); software used to prepare material for publication: SHELXTL.

4-ammoniocyclohexanol–(4-hydroxycyclohexyl)carbamate (1/1) top

Crystal data top

C₆H₁₄NO⁺·C₇H₁₂NO₃⁻	F(000) = 600
M_r = 274.36	D_x = 1.268 Mg m⁻³
Monoclinic, P2₁/c	Melting point: 377 K
Hall symbol: -P 2ybc	Mo Kα radiation, λ = 0.71073 Å
a = 6.3452 (2) Å	Cell parameters from 4934 reflections
b = 18.6256 (6) Å	θ = 2.8–27.5°
c = 12.1664 (4) Å	µ = 0.09 mm⁻¹
β = 92.284 (2)°	T = 120 K
V = 1436.72 (8) Å³	Plate, yellow
Z = 4	0.22 × 0.12 × 0.04 mm

Data collection top

SMART 6k CCD area-detector diffractometer	3308 independent reflections
Radiation source: fine-focus sealed tube	2537 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.038
Detector resolution: 8 pixels mm^-1	θ_max = 27.5°, θ_min = 2.0°
ω scans	h = −7→8
Absorption correction: multi-scan (SADABS; Bruker, 2001)	k = −24→24
T_min = 0.927, T_max = 1.000	l = −15→15
19783 measured reflections

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.037	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.102	All H-atom parameters refined
S = 1.01	w = 1/[σ²(F_o²) + (0.0538P)² + 0.3252P] where P = (F_o² + 2F_c²)/3
3308 reflections	(Δ/σ)_max = 0.001
276 parameters	Δρ_max = 0.27 e Å⁻³
0 restraints	Δρ_min = −0.18 e Å⁻³

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. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > σ(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
O3	−0.46270 (13)	0.63687 (5)	0.01886 (7)	0.0216 (2)
O2	−0.15113 (14)	0.58448 (5)	0.05544 (7)	0.0223 (2)
O1	0.35337 (16)	0.73442 (5)	0.48724 (8)	0.0300 (2)
N1'	0.74068 (18)	0.46768 (6)	0.91750 (8)	0.0182 (2)
O1'	0.56745 (17)	0.60426 (6)	0.50683 (8)	0.0303 (2)
N1	−0.21577 (18)	0.69590 (6)	0.12248 (9)	0.0227 (2)
C7	−0.27812 (19)	0.63633 (6)	0.06402 (9)	0.0172 (2)
C1	−0.0410 (2)	0.69605 (7)	0.20400 (10)	0.0197 (3)
C1'	0.68231 (19)	0.48446 (7)	0.79946 (10)	0.0182 (3)
C4	0.1752 (2)	0.74117 (7)	0.41197 (10)	0.0220 (3)
C5	0.2403 (2)	0.76883 (8)	0.30124 (11)	0.0290 (3)
C5'	0.4282 (2)	0.54960 (7)	0.67150 (10)	0.0217 (3)
C4'	0.6106 (2)	0.58854 (7)	0.61997 (10)	0.0229 (3)
C6'	0.4831 (2)	0.52980 (7)	0.79140 (10)	0.0206 (3)
C3'	0.8078 (2)	0.54205 (8)	0.62791 (12)	0.0291 (3)
C6	0.0536 (3)	0.77048 (8)	0.21763 (12)	0.0298 (3)
C2'	0.8658 (2)	0.52213 (8)	0.74691 (12)	0.0266 (3)
C3	0.0736 (3)	0.66789 (8)	0.39996 (12)	0.0321 (3)
C2	−0.1096 (2)	0.66843 (9)	0.31494 (12)	0.0310 (3)
H1A	0.066 (2)	0.6656 (8)	0.1757 (12)	0.020 (3)*
H1B	0.658 (2)	0.4379 (7)	0.7637 (11)	0.015 (3)*
H2D	0.893 (2)	0.5668 (9)	0.7913 (13)	0.028 (4)*
H6D	0.506 (2)	0.5722 (8)	0.8348 (12)	0.021 (4)*
H4'	0.636 (2)	0.6353 (8)	0.6590 (12)	0.021 (4)*
H5D	0.400 (2)	0.5061 (8)	0.6273 (12)	0.020 (4)*
H4	0.073 (3)	0.7753 (9)	0.4436 (13)	0.030 (4)*
H3D	0.925 (3)	0.5664 (9)	0.5937 (14)	0.033 (4)*
H5C	0.307 (3)	0.5814 (9)	0.6675 (13)	0.030 (4)*
H115	−0.315 (3)	0.7273 (10)	0.1311 (14)	0.038 (5)*
H114	0.870 (3)	0.4447 (9)	0.9227 (13)	0.031 (4)*
H2A	−0.221 (3)	0.7018 (11)	0.3403 (15)	0.047 (5)*
H112	0.641 (3)	0.4352 (9)	0.9465 (14)	0.038 (5)*
H111	0.756 (2)	0.5090 (9)	0.9608 (13)	0.027 (4)*
H6C	0.370 (2)	0.5034 (8)	0.8226 (12)	0.021 (4)*
H5A	0.352 (3)	0.7351 (10)	0.2737 (15)	0.042 (5)*
H1'	0.498 (3)	0.6467 (10)	0.5041 (15)	0.042 (5)*
H3C	0.776 (3)	0.4966 (11)	0.5837 (15)	0.045 (5)*
H2C	0.988 (3)	0.4894 (9)	0.7499 (13)	0.036 (4)*
H3A	0.188 (3)	0.6337 (10)	0.3776 (14)	0.042 (5)*
H6B	−0.058 (3)	0.8024 (10)	0.2441 (14)	0.035 (4)*
H2B	−0.171 (3)	0.6200 (10)	0.3086 (14)	0.039 (5)*
H6A	0.095 (3)	0.7889 (10)	0.1460 (16)	0.047 (5)*
H3B	0.026 (3)	0.6536 (11)	0.4732 (17)	0.053 (5)*
H1	0.419 (3)	0.7770 (11)	0.4939 (16)	0.049 (5)*
H5B	0.305 (3)	0.8174 (10)	0.3088 (14)	0.042 (5)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O3	0.0175 (5)	0.0204 (4)	0.0262 (5)	−0.0009 (3)	−0.0078 (3)	0.0008 (3)
O2	0.0191 (5)	0.0202 (4)	0.0270 (5)	0.0026 (3)	−0.0060 (4)	−0.0046 (3)
O1	0.0349 (6)	0.0212 (5)	0.0322 (5)	−0.0039 (4)	−0.0202 (4)	0.0027 (4)
N1'	0.0167 (5)	0.0184 (5)	0.0191 (5)	0.0002 (4)	−0.0026 (4)	−0.0002 (4)
O1'	0.0362 (6)	0.0308 (5)	0.0235 (5)	0.0065 (4)	−0.0022 (4)	0.0075 (4)
N1	0.0207 (6)	0.0201 (5)	0.0264 (6)	0.0044 (4)	−0.0096 (4)	−0.0048 (4)
C7	0.0183 (6)	0.0169 (6)	0.0161 (5)	−0.0012 (4)	−0.0022 (4)	0.0021 (4)
C1	0.0179 (6)	0.0203 (6)	0.0202 (6)	0.0010 (5)	−0.0064 (5)	−0.0024 (5)
C1'	0.0176 (6)	0.0193 (6)	0.0176 (6)	0.0000 (5)	−0.0024 (4)	0.0007 (4)
C4	0.0230 (7)	0.0213 (6)	0.0211 (6)	0.0002 (5)	−0.0085 (5)	−0.0019 (5)
C5	0.0296 (8)	0.0294 (7)	0.0272 (7)	−0.0137 (6)	−0.0101 (6)	0.0048 (5)
C5'	0.0187 (6)	0.0248 (6)	0.0211 (6)	0.0023 (5)	−0.0047 (5)	0.0005 (5)
C4'	0.0239 (7)	0.0218 (6)	0.0227 (6)	0.0006 (5)	−0.0041 (5)	0.0039 (5)
C6'	0.0163 (6)	0.0257 (6)	0.0196 (6)	0.0022 (5)	−0.0026 (5)	−0.0002 (5)
C3'	0.0218 (7)	0.0360 (8)	0.0297 (7)	0.0044 (6)	0.0044 (6)	0.0145 (6)
C6	0.0380 (8)	0.0245 (7)	0.0258 (7)	−0.0089 (6)	−0.0134 (6)	0.0050 (5)
C2'	0.0159 (6)	0.0324 (7)	0.0311 (7)	0.0008 (5)	−0.0021 (5)	0.0113 (6)
C3	0.0432 (9)	0.0297 (7)	0.0223 (7)	−0.0158 (7)	−0.0113 (6)	0.0072 (6)
C2	0.0318 (8)	0.0352 (8)	0.0253 (7)	−0.0162 (6)	−0.0065 (6)	0.0024 (6)

Geometric parameters (Å, º) top

O3—C7	1.2737 (14)	C5—H5A	1.016 (19)
O2—C7	1.2647 (15)	C5—H5B	0.996 (19)
O1—C4	1.4316 (15)	C5'—C4'	1.5224 (19)
O1—H1	0.90 (2)	C5'—C6'	1.5314 (17)
N1'—C1'	1.5016 (15)	C5'—H5D	0.984 (15)
N1'—H114	0.924 (18)	C5'—H5C	0.971 (17)
N1'—H112	0.953 (18)	C4'—C3'	1.5215 (19)
N1'—H111	0.937 (17)	C4'—H4'	1.002 (15)
O1'—C4'	1.4231 (15)	C6'—H6D	0.959 (15)
O1'—H1'	0.905 (19)	C6'—H6C	0.961 (16)
N1—C7	1.3679 (15)	C3'—C2'	1.5253 (19)
N1—C1	1.4578 (15)	C3'—H3D	0.980 (18)
N1—H115	0.869 (19)	C3'—H3C	1.019 (19)
C1—C6	1.5170 (18)	C6—H6B	0.990 (18)
C1—C2	1.5240 (19)	C6—H6A	0.982 (19)
C1—H1A	0.958 (15)	C2'—H2D	1.003 (16)
C1'—C6'	1.5198 (17)	C2'—H2C	0.984 (18)
C1'—C2'	1.5216 (18)	C3—C2	1.5249 (19)
C1'—H1B	0.979 (14)	C3—H3A	1.011 (19)
C4—C3	1.5141 (18)	C3—H3B	0.99 (2)
C4—C5	1.5151 (19)	C2—H2A	1.00 (2)
C4—H4	0.996 (16)	C2—H2B	0.983 (18)
C5—C6	1.5310 (19)

C4—O1—H1	109.3 (12)	H5D—C5'—H5C	110.4 (13)
C1'—N1'—H114	110.2 (10)	O1'—C4'—C3'	107.74 (11)
C1'—N1'—H112	110.1 (10)	O1'—C4'—C5'	112.09 (11)
H114—N1'—H112	106.3 (14)	C3'—C4'—C5'	109.85 (11)
C1'—N1'—H111	112.6 (9)	O1'—C4'—H4'	107.5 (8)
H114—N1'—H111	105.6 (14)	C3'—C4'—H4'	110.5 (8)
H112—N1'—H111	111.7 (14)	C5'—C4'—H4'	109.1 (8)
C4'—O1'—H1'	106.9 (12)	C1'—C6'—C5'	110.64 (10)
C7—N1—C1	123.48 (11)	C1'—C6'—H6D	108.3 (9)
C7—N1—H115	114.4 (12)	C5'—C6'—H6D	110.5 (9)
C1—N1—H115	116.9 (12)	C1'—C6'—H6C	108.8 (9)
O2—C7—O3	123.25 (11)	C5'—C6'—H6C	110.8 (9)
O2—C7—N1	119.36 (11)	H6D—C6'—H6C	107.7 (12)
O3—C7—N1	117.38 (11)	C4'—C3'—C2'	111.42 (12)
N1—C1—C6	111.28 (10)	C4'—C3'—H3D	110.3 (10)
N1—C1—C2	111.45 (11)	C2'—C3'—H3D	110.9 (10)
C6—C1—C2	109.71 (11)	C4'—C3'—H3C	107.1 (11)
N1—C1—H1A	106.5 (8)	C2'—C3'—H3C	109.5 (10)
C6—C1—H1A	107.3 (9)	H3D—C3'—H3C	107.4 (14)
C2—C1—H1A	110.5 (9)	C1—C6—C5	110.28 (11)
N1'—C1'—C6'	110.50 (10)	C1—C6—H6B	107.4 (10)
N1'—C1'—C2'	109.52 (10)	C5—C6—H6B	110.0 (10)
C6'—C1'—C2'	111.39 (10)	C1—C6—H6A	110.0 (11)
N1'—C1'—H1B	105.6 (8)	C5—C6—H6A	111.6 (11)
C6'—C1'—H1B	110.2 (8)	H6B—C6—H6A	107.4 (15)
C2'—C1'—H1B	109.4 (8)	C1'—C2'—C3'	110.58 (11)
O1—C4—C3	107.75 (10)	C1'—C2'—H2D	106.0 (9)
O1—C4—C5	111.25 (11)	C3'—C2'—H2D	109.9 (9)
C3—C4—C5	110.54 (11)	C1'—C2'—H2C	108.2 (10)
O1—C4—H4	108.5 (9)	C3'—C2'—H2C	110.2 (10)
C3—C4—H4	109.3 (9)	H2D—C2'—H2C	111.9 (13)
C5—C4—H4	109.4 (9)	C4—C3—C2	111.69 (12)
C4—C5—C6	111.49 (12)	C4—C3—H3A	106.7 (10)
C4—C5—H5A	107.6 (10)	C2—C3—H3A	111.0 (10)
C6—C5—H5A	109.1 (10)	C4—C3—H3B	107.4 (12)
C4—C5—H5B	110.7 (10)	C2—C3—H3B	111.2 (12)
C6—C5—H5B	110.5 (10)	H3A—C3—H3B	108.7 (15)
H5A—C5—H5B	107.4 (14)	C1—C2—C3	111.49 (12)
C4'—C5'—C6'	111.03 (10)	C1—C2—H2A	107.1 (11)
C4'—C5'—H5D	107.0 (8)	C3—C2—H2A	109.0 (11)
C6'—C5'—H5D	110.6 (8)	C1—C2—H2B	111.4 (10)
C4'—C5'—H5C	107.6 (9)	C3—C2—H2B	109.5 (10)
C6'—C5'—H5C	110.2 (9)	H2A—C2—H2B	108.2 (15)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1′—H1′···O1	0.90 (2)	1.88 (2)	2.784 (2)	176 (1)
O1—H1···O3ⁱ	0.90 (2)	1.79 (2)	2.687 (1)	175 (2)
N1′—H111···O2ⁱⁱ	0.94 (2)	1.90 (2)	2.816 (1)	167 (1)
N1′—H112···O3ⁱⁱⁱ	0.95 (2)	1.82 (2)	2.7590 (1)	170 (1)
N1′—H114···O2^iv	0.92 (2)	1.87 (2)	2.7870 (1)	169 (1)
C6′—H6D···O3ⁱⁱ	0.96 (2)	2.54 (1)	3.417 (1)	152 (1)

Symmetry codes: (i) x+1, −y+3/2, z+1/2; (ii) x+1, y, z+1; (iii) −x, −y+1, −z+1; (iv) −x+1, −y+1, −z+1.

Acknowledgements

AD thanks the CSIR for fellowship support. RM thanks the ORS for support. JAKH thanks the EPSRC for a Senior Research Fellowship. GRD thanks DST for financial assistance.

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