(±)-Adamantane-1,2-diyl diacetate

The first structural analysis of a 1,2-disubstituted adamantane, (±)-adamantane-1,2-diyl diacetate, C₁₄H₂₀O₄, is reported. The molecules pack in columns which are held together by inter- and intracolumn C—H...O interactions.

Key indicators

• Single-crystal X-ray study
• T = 85 K
• Mean [sigma](C-C) = 0.001 Å
• R factor = 0.033
• wR factor = 0.097
• Data-to-parameter ratio = 24.2

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT062_ALERT_4_C Rescale T(min) & T(max) by .....................       0.98
PLAT094_ALERT_2_C Ratio of Maximum / Minimum Residual Density ....       2.81
PLAT125_ALERT_4_C No _symmetry_space_group_name_Hall Given .......          ?
PLAT380_ALERT_4_C Check Incorrectly? Oriented X(sp2)-Methyl Moiety         C4
PLAT790_ALERT_4_C Centre of Gravity not Within Unit Cell: Resd.  #          1
              C14 H20 O4

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   5 ALERT level C = Check and explain
   0 ALERT level G = General alerts; check

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

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S1. Comment

The title compound, (I) (Fig. 1), was prepared as an intermediate in the synthesis of adamantane-1,2-diol as part of a study of binding selectivity of molecularly imprinted polymers with conformationally restricted molecules. Compound (I) crystallizes in the monoclinic space group P21/c, confirming the presence of both enantiomers in the crystalline material. The C—C bond distances within the adamantane ring range from 1.5293 (12) to 1.5402 (12) Å, hence showing a greater variety of values than those in unsubstituted adamantane (1.528–1.530 Å; Amoureux & Foulon, 1987). The molecules are arranged in columns, which run parallel to the a axis. The only intracolumn interaction of any note is that between carbonyl atom O3 and atom H10B (2.682 Å) of a neighbouring molecule at (−1 + x,y,z). Carbonyl atom O4 is involved in interactions with H6(x, 1/2 − y, −1/2 + z) (2.664 Å) and H9(−x, −y, 1 − z) (2.646 Å) of molecules in adjacent columns, while O3 also engages in an intercolumn interaction with H2A(−1 − x, −y, 2 − z) (2.450 Å).

S2. Experimental

Adamantane-1,2-diacetate was prepared as described previously (McKervey et al., 1971; Janjatovic & Majerski, 1980) and was crystallized from a chloroform/2-propanol mixture as large colourless blocks, which were cut to provide suitable crystals for structural analysis.

S3. Refinement

All H atoms were included in calculated positions (C—H = 0.96 Å for methyl H atoms, 0.97 Å for methylene H atoms and 0.98 Å for methine H atoms) and were refined as riding atoms with U_iso(H) = 1.2U_eq(parent atom, methylene and methine H atoms) or U_iso(H) = 1.5U_eq(parent atom, methyl H atoms).

Computing details

Data collection: APEX-II (Bruker, 2004); cell refinement: APEX-II and SAINT (Bruker, 2001); data reduction: SAINT; program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: WinGX (Farrugia, 1999); software used to prepare material for publication: WinGX.

Figures

	Fig. 1. The structure of (I), with displacement ellipsoids drawn at the 50% probability level.
	Fig. 2. Packing diagram viewed down the a axis. Close interactions are indicated as dotted lines.

(±)-adamantane-1,2-diyl diacetate

Crystal data

C14H20O4	F(000) = 544
Mr = 252.30	Dx = 1.324 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71069 Å
a = 8.699 (5) Å	Cell parameters from 9961 reflections
b = 12.618 (5) Å	θ = 2.9–33.3°
c = 11.835 (5) Å	µ = 0.10 mm^−1
β = 102.934 (5)°	T = 85 K
V = 1266.1 (10) Å^3	Irregular chip, colourless
Z = 4	0.43 × 0.23 × 0.22 mm

Data collection

Bruker Kappa-APEX-II area-detector diffractometer	3997 independent reflections
Radiation source: fine-focus sealed tube	3699 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.022
ϕ and ω scans	θmax = 33.3°, θmin = 2.4°
Absorption correction: multi-scan (SADABS; Bruker, 2001)	h = −12→12
Tmin = 0.919, Tmax = 1.000	k = −14→18
26090 measured reflections	l = −17→17

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)] = 0.033	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.097	H-atom parameters constrained
S = 1.03	w = 1/[σ^2(Fo^2) + (0.0517P)^2 + 0.3507P] where P = (Fo^2 + 2Fc^2)/3
3997 reflections	(Δ/σ)max < 0.001
165 parameters	Δρmax = 0.44 e Å^−3
0 restraints	Δρmin = −0.16 e Å^−3

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq
O1	−0.25583 (6)	0.01495 (4)	0.81193 (5)	0.01594 (11)
O2	−0.33618 (6)	0.12926 (4)	0.61053 (5)	0.01474 (11)
C9	0.09378 (8)	0.04534 (6)	0.71586 (6)	0.01481 (14)
H9	0.1582	−0.0110	0.6930	0.018*
C11	0.06989 (8)	0.24196 (6)	0.74048 (6)	0.01531 (14)
H11	0.1186	0.3108	0.7326	0.018*
C1	−0.38855 (8)	0.01489 (6)	0.85309 (6)	0.01675 (14)
O4	−0.28263 (7)	0.14644 (5)	0.43214 (5)	0.02051 (13)
O3	−0.44730 (8)	0.09334 (5)	0.88291 (6)	0.02790 (15)
C6	−0.18213 (8)	0.11664 (5)	0.80057 (6)	0.01327 (13)
H6	−0.2452	0.1739	0.8231	0.016*
C10	0.16906 (8)	0.15341 (6)	0.70285 (7)	0.01673 (14)
H10A	0.1748	0.1641	0.6227	0.020*
H10B	0.2755	0.1554	0.7504	0.020*
C14	−0.07328 (8)	0.04181 (6)	0.63738 (6)	0.01357 (13)
H14A	−0.0679	0.0511	0.5570	0.016*
H14B	−0.1218	−0.0263	0.6449	0.016*
C2	−0.45344 (10)	−0.09514 (7)	0.85567 (8)	0.02358 (17)
H2A	−0.4908	−0.1046	0.9254	0.035*
H2B	−0.3719	−0.1459	0.8536	0.035*
H2C	−0.5391	−0.1053	0.7896	0.035*
C12	−0.09753 (8)	0.23938 (6)	0.66314 (6)	0.01427 (13)
H12A	−0.1613	0.2945	0.6869	0.017*
H12B	−0.0932	0.2522	0.5831	0.017*
C5	−0.17133 (8)	0.13073 (5)	0.67405 (6)	0.01207 (13)
C8	0.08447 (9)	0.02928 (6)	0.84270 (6)	0.01633 (14)
H8A	0.1897	0.0309	0.8921	0.020*
H8B	0.0382	−0.0393	0.8516	0.020*
C7	−0.01647 (8)	0.11724 (6)	0.87894 (6)	0.01481 (14)
H7	−0.0234	0.1064	0.9596	0.018*
C13	0.05908 (8)	0.22556 (6)	0.86704 (7)	0.01679 (14)
H13A	−0.0042	0.2814	0.8901	0.020*
H13B	0.1637	0.2285	0.9173	0.020*
C4	−0.55074 (9)	0.14430 (7)	0.45141 (7)	0.02208 (16)
H4A	−0.5800	0.2103	0.4122	0.033*
H4B	−0.6003	0.1385	0.5159	0.033*
H4C	−0.5843	0.0867	0.3987	0.033*
C3	−0.37498 (8)	0.14026 (6)	0.49433 (6)	0.01568 (14)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0174 (2)	0.0134 (2)	0.0196 (3)	−0.00240 (18)	0.00967 (19)	−0.00010 (19)
O2	0.0115 (2)	0.0170 (2)	0.0158 (2)	0.00017 (17)	0.00319 (17)	−0.00006 (19)
C9	0.0139 (3)	0.0151 (3)	0.0158 (3)	0.0030 (2)	0.0040 (2)	−0.0007 (2)
C11	0.0143 (3)	0.0137 (3)	0.0184 (3)	−0.0022 (2)	0.0047 (2)	−0.0002 (2)
C1	0.0154 (3)	0.0207 (4)	0.0153 (3)	−0.0015 (2)	0.0058 (2)	0.0027 (3)
O4	0.0179 (2)	0.0268 (3)	0.0172 (3)	0.0025 (2)	0.0046 (2)	0.0019 (2)
O3	0.0258 (3)	0.0239 (3)	0.0401 (4)	0.0023 (2)	0.0204 (3)	0.0016 (3)
C6	0.0153 (3)	0.0111 (3)	0.0149 (3)	−0.0013 (2)	0.0064 (2)	−0.0008 (2)
C10	0.0128 (3)	0.0193 (3)	0.0189 (3)	0.0001 (2)	0.0055 (2)	0.0004 (3)
C14	0.0143 (3)	0.0128 (3)	0.0141 (3)	0.0016 (2)	0.0043 (2)	−0.0017 (2)
C2	0.0248 (4)	0.0229 (4)	0.0259 (4)	−0.0081 (3)	0.0119 (3)	0.0004 (3)
C12	0.0143 (3)	0.0118 (3)	0.0175 (3)	−0.0002 (2)	0.0051 (2)	0.0015 (2)
C5	0.0109 (3)	0.0122 (3)	0.0135 (3)	0.0003 (2)	0.0035 (2)	−0.0003 (2)
C8	0.0178 (3)	0.0154 (3)	0.0153 (3)	0.0024 (2)	0.0026 (2)	0.0010 (2)
C7	0.0172 (3)	0.0149 (3)	0.0127 (3)	−0.0009 (2)	0.0041 (2)	−0.0008 (2)
C13	0.0178 (3)	0.0156 (3)	0.0171 (3)	−0.0027 (2)	0.0042 (2)	−0.0034 (3)
C4	0.0136 (3)	0.0279 (4)	0.0231 (4)	0.0011 (3)	0.0006 (3)	0.0004 (3)
C3	0.0149 (3)	0.0143 (3)	0.0171 (3)	0.0013 (2)	0.0019 (2)	−0.0001 (2)

Geometric parameters (Å, º)

O1—C1	1.3499 (10)	C14—C5	1.5299 (10)
O1—C6	1.4539 (9)	C14—H14A	0.9700
O2—C3	1.3478 (11)	C14—H14B	0.9700
O2—C5	1.4626 (11)	C2—H2A	0.9600
C9—C8	1.5347 (12)	C2—H2B	0.9600
C9—C10	1.5354 (11)	C2—H2C	0.9600
C9—C14	1.5402 (12)	C12—C5	1.5315 (11)
C9—H9	0.9800	C12—H12A	0.9700
C11—C13	1.5358 (12)	C12—H12B	0.9700
C11—C10	1.5372 (11)	C8—C7	1.5348 (11)
C11—C12	1.5373 (12)	C8—H8A	0.9700
C11—H11	0.9800	C8—H8B	0.9700
C1—O3	1.2027 (11)	C7—C13	1.5366 (11)
C1—C2	1.5016 (12)	C7—H7	0.9800
O4—C3	1.2074 (10)	C13—H13A	0.9700
C6—C7	1.5293 (12)	C13—H13B	0.9700
C6—C5	1.5315 (12)	C4—C3	1.5002 (13)
C6—H6	0.9800	C4—H4A	0.9600
C10—H10A	0.9700	C4—H4B	0.9600
C10—H10B	0.9700	C4—H4C	0.9600
C1—O1—C6	117.67 (6)	H2B—C2—H2C	109.5
C3—O2—C5	121.06 (5)	C5—C12—C11	109.14 (6)
C8—C9—C10	109.41 (6)	C5—C12—H12A	109.9
C8—C9—C14	109.68 (6)	C11—C12—H12A	109.9
C10—C9—C14	109.34 (6)	C5—C12—H12B	109.9
C8—C9—H9	109.5	C11—C12—H12B	109.9
C10—C9—H9	109.5	H12A—C12—H12B	108.3
C14—C9—H9	109.5	O2—C5—C14	112.93 (6)
C13—C11—C10	110.21 (6)	O2—C5—C12	110.45 (6)
C13—C11—C12	108.73 (6)	C14—C5—C12	111.21 (6)
C10—C11—C12	109.30 (6)	O2—C5—C6	103.50 (6)
C13—C11—H11	109.5	C14—C5—C6	110.63 (6)
C10—C11—H11	109.5	C12—C5—C6	107.75 (6)
C12—C11—H11	109.5	C9—C8—C7	109.67 (6)
O3—C1—O1	124.01 (7)	C9—C8—H8A	109.7
O3—C1—C2	124.66 (7)	C7—C8—H8A	109.7
O1—C1—C2	111.32 (7)	C9—C8—H8B	109.7
O1—C6—C7	108.88 (6)	C7—C8—H8B	109.7
O1—C6—C5	108.52 (6)	H8A—C8—H8B	108.2
C7—C6—C5	109.68 (6)	C6—C7—C8	110.32 (6)
O1—C6—H6	109.9	C6—C7—C13	108.25 (6)
C7—C6—H6	109.9	C8—C7—C13	109.54 (7)
C5—C6—H6	109.9	C6—C7—H7	109.6
C9—C10—C11	109.69 (6)	C8—C7—H7	109.6
C9—C10—H10A	109.7	C13—C7—H7	109.6
C11—C10—H10A	109.7	C11—C13—C7	109.27 (6)
C9—C10—H10B	109.7	C11—C13—H13A	109.8
C11—C10—H10B	109.7	C7—C13—H13A	109.8
H10A—C10—H10B	108.2	C11—C13—H13B	109.8
C5—C14—C9	108.57 (6)	C7—C13—H13B	109.8
C5—C14—H14A	110.0	H13A—C13—H13B	108.3
C9—C14—H14A	110.0	C3—C4—H4A	109.5
C5—C14—H14B	110.0	C3—C4—H4B	109.5
C9—C14—H14B	110.0	H4A—C4—H4B	109.5
H14A—C14—H14B	108.4	C3—C4—H4C	109.5
C1—C2—H2A	109.5	H4A—C4—H4C	109.5
C1—C2—H2B	109.5	H4B—C4—H4C	109.5
H2A—C2—H2B	109.5	O4—C3—O2	125.44 (7)
C1—C2—H2C	109.5	O4—C3—C4	123.93 (8)
H2A—C2—H2C	109.5	O2—C3—C4	110.64 (6)