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The central three-membered ring in the title compound, trans-1,1',1''-cyclopropane-1,2,3-triyltris(cyclopropanol), C12H18O3, shows pronounced asymmetry of the bond lengths, which is induced by the different orientations of the substituents. A network of hydrogen bonds links the molecules into sheets.
Supporting information
CCDC reference: 170199
Crystals of (I) (Meijere & Kozhushkov, 2000) were obtained by slow evaporation
of a solution in diethyl ether.
Data collection: SMART (Bruker, 1997); cell refinement: SAINT (Bruker, 1997); data reduction: SHELXTL (Bruker, 1997); program(s) used to solve structure: SHELXTL; program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.
trans-1,2,3-tris-(1'-hydroxycyclopropyl)cyclopropane
top
Crystal data top
C12H18O3 | Dx = 1.259 Mg m−3 |
Mr = 210.26 | Melting point = 129–130 K |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
a = 12.6464 (3) Å | Cell parameters from 511 reflections |
b = 8.4615 (2) Å | θ = 2.5–29.1° |
c = 10.4323 (2) Å | µ = 0.09 mm−1 |
β = 96.578 (1)° | T = 120 K |
V = 1108.99 (4) Å3 | Prism, colourless |
Z = 4 | 0.62 × 0.14 × 0.14 mm |
F(000) = 456 | |
Data collection top
Bruker SMART CCD 1K diffractometer | 2555 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.033 |
Graphite monochromator | θmax = 30.3°, θmin = 1.6° |
Detector resolution: 8 pixels mm-1 | h = −17→16 |
ω–scan | k = −11→11 |
10828 measured reflections | l = −14→14 |
3064 independent 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)] = 0.042 | Hydrogen site location: difference Fourier map |
wR(F2) = 0.103 | All H-atom parameters refined |
S = 1.10 | w = 1/[σ2(Fo2) + (0.0396P)2 + 0.4841P] where P = (Fo2 + 2Fc2)/3 |
3064 reflections | (Δ/σ)max = 0.001 |
208 parameters | Δρmax = 0.32 e Å−3 |
0 restraints | Δρmin = −0.23 e Å−3 |
Crystal data top
C12H18O3 | V = 1108.99 (4) Å3 |
Mr = 210.26 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 12.6464 (3) Å | µ = 0.09 mm−1 |
b = 8.4615 (2) Å | T = 120 K |
c = 10.4323 (2) Å | 0.62 × 0.14 × 0.14 mm |
β = 96.578 (1)° | |
Data collection top
Bruker SMART CCD 1K diffractometer | 2555 reflections with I > 2σ(I) |
10828 measured reflections | Rint = 0.033 |
3064 independent reflections | |
Refinement top
R[F2 > 2σ(F2)] = 0.042 | 0 restraints |
wR(F2) = 0.103 | All H-atom parameters refined |
S = 1.10 | Δρmax = 0.32 e Å−3 |
3064 reflections | Δρmin = −0.23 e Å−3 |
208 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. |
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 | Uiso*/Ueq | |
O1 | 0.84923 (7) | 0.45925 (10) | 0.06654 (9) | 0.01897 (19) | |
O2 | 0.70894 (8) | 0.31988 (10) | 0.21164 (8) | 0.0206 (2) | |
O3 | 0.75775 (7) | 1.02880 (10) | 0.31831 (9) | 0.01879 (19) | |
C1 | 0.76243 (9) | 0.67846 (13) | 0.16650 (11) | 0.0135 (2) | |
C2 | 0.68786 (9) | 0.59524 (13) | 0.24978 (11) | 0.0141 (2) | |
C3 | 0.74427 (9) | 0.74430 (13) | 0.29710 (11) | 0.0139 (2) | |
C4 | 0.86449 (9) | 0.60215 (13) | 0.13911 (11) | 0.0149 (2) | |
C5 | 0.96650 (10) | 0.61334 (16) | 0.22856 (13) | 0.0208 (3) | |
C6 | 0.95383 (10) | 0.70138 (15) | 0.10029 (12) | 0.0191 (2) | |
C7 | 0.71554 (9) | 0.43754 (13) | 0.30985 (11) | 0.0153 (2) | |
C8 | 0.79725 (11) | 0.41681 (15) | 0.42510 (13) | 0.0224 (3) | |
C9 | 0.67936 (11) | 0.39635 (15) | 0.43774 (12) | 0.0214 (3) | |
C10 | 0.68713 (9) | 0.89786 (13) | 0.30778 (11) | 0.0148 (2) | |
C11 | 0.58054 (10) | 0.93183 (15) | 0.23469 (13) | 0.0212 (3) | |
C12 | 0.59075 (10) | 0.90901 (15) | 0.38025 (13) | 0.0216 (3) | |
H1O | 0.8107 (16) | 0.403 (2) | 0.1049 (19) | 0.041 (5)* | |
H2O | 0.7258 (14) | 0.231 (2) | 0.2480 (18) | 0.037 (5)* | |
H3O | 0.7909 (17) | 1.028 (2) | 0.398 (2) | 0.050 (6)* | |
H1 | 0.7263 (11) | 0.7376 (17) | 0.0932 (14) | 0.014 (3)* | |
H2 | 0.6123 (12) | 0.6036 (17) | 0.2184 (14) | 0.017 (4)* | |
H3 | 0.8033 (12) | 0.7290 (18) | 0.3652 (14) | 0.019 (4)* | |
H51 | 0.9672 (12) | 0.6761 (19) | 0.3075 (16) | 0.025 (4)* | |
H52 | 1.0128 (14) | 0.519 (2) | 0.2335 (17) | 0.030 (4)* | |
H61 | 0.9916 (12) | 0.6614 (18) | 0.0339 (15) | 0.021 (4)* | |
H62 | 0.9447 (12) | 0.8155 (19) | 0.1030 (15) | 0.021 (4)* | |
H81 | 0.8405 (13) | 0.322 (2) | 0.4267 (15) | 0.027 (4)* | |
H82 | 0.8334 (14) | 0.509 (2) | 0.4654 (16) | 0.029 (4)* | |
H91 | 0.6547 (12) | 0.288 (2) | 0.4510 (15) | 0.024 (4)* | |
H92 | 0.6434 (13) | 0.478 (2) | 0.4803 (16) | 0.029 (4)* | |
H111 | 0.5435 (13) | 0.848 (2) | 0.1792 (16) | 0.027 (4)* | |
H112 | 0.5685 (13) | 1.0399 (19) | 0.2041 (16) | 0.024 (4)* | |
H121 | 0.5853 (13) | 1.003 (2) | 0.4353 (16) | 0.029 (4)* | |
H122 | 0.5631 (13) | 0.809 (2) | 0.4128 (16) | 0.031 (4)* | |
Atomic displacement parameters (Å2) top | U11 | U22 | U33 | U12 | U13 | U23 |
O1 | 0.0249 (4) | 0.0132 (4) | 0.0200 (4) | 0.0005 (3) | 0.0076 (3) | −0.0031 (3) |
O2 | 0.0334 (5) | 0.0102 (4) | 0.0185 (4) | −0.0005 (3) | 0.0048 (4) | −0.0013 (3) |
O3 | 0.0247 (5) | 0.0112 (4) | 0.0210 (4) | −0.0015 (3) | 0.0047 (4) | 0.0007 (3) |
C1 | 0.0160 (5) | 0.0120 (5) | 0.0127 (5) | 0.0014 (4) | 0.0027 (4) | 0.0009 (4) |
C2 | 0.0149 (5) | 0.0114 (5) | 0.0162 (5) | 0.0001 (4) | 0.0025 (4) | 0.0003 (4) |
C3 | 0.0157 (5) | 0.0109 (5) | 0.0155 (5) | 0.0010 (4) | 0.0034 (4) | −0.0003 (4) |
C4 | 0.0177 (5) | 0.0123 (5) | 0.0150 (5) | 0.0017 (4) | 0.0036 (4) | −0.0007 (4) |
C5 | 0.0183 (6) | 0.0238 (6) | 0.0203 (6) | 0.0040 (5) | 0.0019 (4) | −0.0001 (5) |
C6 | 0.0182 (6) | 0.0184 (6) | 0.0216 (6) | −0.0003 (4) | 0.0060 (4) | 0.0001 (5) |
C7 | 0.0192 (5) | 0.0112 (5) | 0.0161 (5) | 0.0000 (4) | 0.0040 (4) | −0.0004 (4) |
C8 | 0.0260 (6) | 0.0156 (5) | 0.0242 (6) | 0.0011 (5) | −0.0035 (5) | 0.0038 (5) |
C9 | 0.0296 (7) | 0.0170 (5) | 0.0186 (6) | 0.0010 (5) | 0.0074 (5) | 0.0028 (5) |
C10 | 0.0173 (5) | 0.0116 (5) | 0.0161 (5) | 0.0016 (4) | 0.0046 (4) | 0.0002 (4) |
C11 | 0.0192 (6) | 0.0201 (6) | 0.0244 (6) | 0.0066 (5) | 0.0031 (5) | 0.0031 (5) |
C12 | 0.0223 (6) | 0.0209 (6) | 0.0233 (6) | 0.0045 (5) | 0.0101 (5) | 0.0012 (5) |
Geometric parameters (Å, º) top
O1—C4 | 1.428 (1) | O1—H1O | 0.82 (2) |
O2—C7 | 1.424 (1) | O2—H2O | 0.86 (2) |
O3—C10 | 1.419 (1) | O3—H3O | 0.89 (2) |
C1—C4 | 1.500 (2) | C1—H1 | 0.98 (1) |
C1—C3 | 1.514 (2) | C2—H2 | 0.98 (2) |
C1—C2 | 1.526 (2) | C3—H3 | 0.98 (2) |
C2—C7 | 1.499 (2) | C5—H51 | 0.98 (2) |
C2—C3 | 1.504 (2) | C5—H52 | 0.99 (2) |
C3—C10 | 1.497 (2) | C6—H61 | 0.95 (2) |
C4—C6 | 1.500 (2) | C6—H62 | 0.97 (2) |
C4—C5 | 1.506 (2) | C8—H81 | 0.97 (2) |
C5—C6 | 1.524 (2) | C8—H82 | 0.98 (2) |
C7—C9 | 1.500 (2) | C9—H91 | 0.98 (2) |
C7—C8 | 1.503 (2) | C9—H92 | 0.96 (2) |
C8—C9 | 1.522 (2) | C11—H111 | 1.00 (2) |
C10—C11 | 1.499 (2) | C11—H112 | 0.98 (2) |
C10—C12 | 1.509 (2) | C12—H121 | 0.99 (2) |
C11—C12 | 1.522 (2) | C12—H122 | 0.99 (2) |
| | | |
C4—C1—C3 | 123.5 (1) | C2—C1—H1 | 114.6 (8) |
C4—C1—C2 | 120.76 (9) | C7—C2—H2 | 112.2 (9) |
C3—C1—C2 | 59.33 (7) | C3—C2—H2 | 117.3 (9) |
C7—C2—C3 | 122.0 (1) | C1—C2—H2 | 114.9 (9) |
C7—C2—C1 | 121.3 (1) | C10—C3—H3 | 113.3 (9) |
C3—C2—C1 | 59.94 (7) | C2—C3—H3 | 114.9 (9) |
C10—C3—C2 | 122.5 (1) | C1—C3—H3 | 115.0 (9) |
C10—C3—C1 | 120.7 (1) | C4—C5—H51 | 118.7 (9) |
C2—C3—C1 | 60.73 (7) | C6—C5—H51 | 118 (1) |
O1—C4—C1 | 113.5 (1) | C4—C5—H52 | 116 (1) |
O1—C4—C6 | 113.02 (9) | C6—C5—H52 | 116 (1) |
C1—C4—C6 | 120.1 (1) | H51—C5—H52 | 117 (1) |
O1—C4—C5 | 115.8 (1) | C4—C6—H61 | 117.1 (9) |
C1—C4—C5 | 123.4 (1) | C5—C6—H61 | 117.1 (9) |
C6—C4—C5 | 60.92 (8) | C4—C6—H62 | 116.9 (9) |
C4—C5—C6 | 59.35 (8) | C5—C6—H62 | 117.4 (9) |
C4—C6—C5 | 59.74 (8) | H61—C6—H62 | 117 (1) |
O2—C7—C2 | 109.27 (9) | C7—C8—H81 | 116 (1) |
O2—C7—C9 | 118.6 (1) | C9—C8—H81 | 117 (1) |
C2—C7—C9 | 119.9 (1) | C7—C8—H82 | 120 (1) |
O2—C7—C8 | 118.2 (1) | C9—C8—H82 | 118 (1) |
C2—C7—C8 | 123.0 (1) | H81—C8—H82 | 115 (1) |
C9—C7—C8 | 60.87 (9) | C7—C9—H91 | 118.5 (9) |
C7—C8—C9 | 59.47 (8) | C8—C9—H91 | 116.7 (9) |
C7—C9—C8 | 59.66 (8) | C7—C9—H92 | 117 (1) |
O3—C10—C3 | 112.23 (9) | C8—C9—H92 | 119 (1) |
O3—C10—C11 | 114.3 (1) | H91—C9—H92 | 115 (1) |
C3—C10—C11 | 122.8 (1) | C10—C11—H111 | 119.7 (9) |
O3—C10—C12 | 116.7 (1) | C12—C11—H111 | 118 (1) |
C3—C10—C12 | 121.1 (1) | C10—C11—H112 | 116 (1) |
C11—C10—C12 | 60.78 (8) | C12—C11—H112 | 116 (1) |
C10—C11—C12 | 59.95 (8) | H111—C11—H112 | 115 (1) |
C10—C12—C11 | 59.27 (8) | C10—C12—H121 | 117 (1) |
C4—O1—H1O | 107 (1) | C11—C12—H121 | 118 (1) |
C7—O2—H2O | 108 (1) | C10—C12—H122 | 117 (1) |
C10—O3—H3O | 107 (1) | C11—C12—H122 | 117 (1) |
C4—C1—H1 | 113.9 (8) | H121—C12—H122 | 116 (1) |
C3—C1—H1 | 114.1 (8) | | |
| | | |
C4—C1—C2—C7 | 1.8 (2) | C1—C2—C7—O2 | −70.5 (1) |
C3—C1—C2—C7 | −111.4 (1) | C3—C2—C7—C9 | 75.8 (2) |
C4—C1—C2—C3 | 113.3 (1) | C1—C2—C7—C9 | 147.7 (1) |
C7—C2—C3—C10 | −140.1 (1) | C3—C2—C7—C8 | 3.1 (2) |
C1—C2—C3—C10 | 109.7 (1) | C1—C2—C7—C8 | 74.9 (2) |
C7—C2—C3—C1 | 110.2 (1) | O2—C7—C8—C9 | −108.9 (1) |
C4—C1—C3—C10 | 138.8 (1) | C2—C7—C8—C9 | 108.6 (1) |
C2—C1—C3—C10 | −112.6 (1) | O2—C7—C9—C8 | 108.2 (1) |
C4—C1—C3—C2 | −108.7 (1) | C2—C7—C9—C8 | −113.5 (1) |
C3—C1—C4—O1 | 135.3 (1) | C2—C3—C10—O3 | −163.1 (1) |
C2—C1—C4—O1 | 63.8 (1) | C1—C3—C10—O3 | −90.3 (1) |
C3—C1—C4—C6 | −86.5 (1) | C2—C3—C10—C11 | −20.7 (2) |
C2—C1—C4—C6 | −158.1 (1) | C1—C3—C10—C11 | 52.1 (2) |
C3—C1—C4—C5 | −13.5 (2) | C2—C3—C10—C12 | 52.5 (2) |
C2—C1—C4—C5 | −84.9 (1) | C1—C3—C10—C12 | 125.3 (1) |
O1—C4—C5—C6 | 103.2 (1) | O3—C10—C11—C12 | −108.2 (1) |
C1—C4—C5—C6 | −108.7 (1) | C3—C10—C11—C12 | 110.0 (1) |
O1—C4—C6—C5 | −107.8 (1) | O3—C10—C12—C11 | 104.2 (1) |
C1—C4—C6—C5 | 113.9 (1) | C3—C10—C12—C11 | −112.9 (1) |
C3—C2—C7—O2 | −142.4 (1) | | |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1O···O2 | 0.82 (2) | 1.93 (2) | 2.729 (1) | 166 (2) |
O2—H2O···O3i | 0.86 (2) | 1.88 (2) | 2.744 (1) | 176 (2) |
O3—H3O···O1ii | 0.89 (2) | 1.83 (2) | 2.714 (1) | 174 (2) |
C6—H61···O1iii | 0.948 (16) | 2.584 (16) | 3.475 (2) | 157 (1) |
Symmetry codes: (i) x, y−1, z; (ii) x, −y+3/2, z+1/2; (iii) −x+2, −y+1, −z. |
Experimental details
Crystal data |
Chemical formula | C12H18O3 |
Mr | 210.26 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 120 |
a, b, c (Å) | 12.6464 (3), 8.4615 (2), 10.4323 (2) |
β (°) | 96.578 (1) |
V (Å3) | 1108.99 (4) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.09 |
Crystal size (mm) | 0.62 × 0.14 × 0.14 |
|
Data collection |
Diffractometer | Bruker SMART CCD 1K diffractometer |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 10828, 3064, 2555 |
Rint | 0.033 |
(sin θ/λ)max (Å−1) | 0.711 |
|
Refinement |
R[F2 > 2σ(F2)], wR(F2), S | 0.042, 0.103, 1.10 |
No. of reflections | 3064 |
No. of parameters | 208 |
H-atom treatment | All H-atom parameters refined |
Δρmax, Δρmin (e Å−3) | 0.32, −0.23 |
Selected bond lengths (Å) topO1—C4 | 1.428 (1) | C4—C6 | 1.500 (2) |
O2—C7 | 1.424 (1) | C4—C5 | 1.506 (2) |
O3—C10 | 1.419 (1) | C5—C6 | 1.524 (2) |
C1—C4 | 1.500 (2) | C7—C9 | 1.500 (2) |
C1—C3 | 1.514 (2) | C7—C8 | 1.503 (2) |
C1—C2 | 1.526 (2) | C8—C9 | 1.522 (2) |
C2—C7 | 1.499 (2) | C10—C11 | 1.499 (2) |
C2—C3 | 1.504 (2) | C10—C12 | 1.509 (2) |
C3—C10 | 1.497 (2) | C11—C12 | 1.522 (2) |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1O···O2 | 0.82 (2) | 1.93 (2) | 2.729 (1) | 166 (2) |
O2—H2O···O3i | 0.86 (2) | 1.88 (2) | 2.744 (1) | 176 (2) |
O3—H3O···O1ii | 0.89 (2) | 1.83 (2) | 2.714 (1) | 174 (2) |
C6—H61···O1iii | 0.948 (16) | 2.584 (16) | 3.475 (2) | 157 (1) |
Symmetry codes: (i) x, y−1, z; (ii) x, −y+3/2, z+1/2; (iii) −x+2, −y+1, −z. |
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trans-1,1',1''-Cyclopropane-1,2,3-triyltris(cyclopropanol), (I), has been synthesized as an intermediate product along the route to tris-(cyclopropylidene)cyclopropane in the course of our search for new synthetic approaches to highly strained polyspirocyclopropane derivatives (de Meijere & Kozhushkov, 2000). The compound was obtained in 90% yield from triethyl trans-cyclopropanetricarboxylate using the recently developed Kulinkovich reaction (Kulinkovich & de Meijere, 2000) which transforms an alkoxycarbonyl group into cyclopropanol upon treatment with an excess of ethylmagnesium bromide in the presence of Ti(iPrO)4. \sch
Along with the determination of molecular conformation, the geometry of the symmetrically substituted central cyclopropane (CP) ring was of interest. In molecule (I) we have a relatively rare case of three identical weak π-acceptors connected with three atoms of the central CP-ring. In spite of a great number of reported structures of substituted CP, very few examples of such compounds with identical substituents at all three carbon atoms of CP are available in literature and, for the best of our knowledge, no 1,2,3-tricyclopropylcyclopropane has been described before. The effect of substitution on the geometry of CP ring is relatively well understood and described in terms of different models (see, for example, Allen, 1980; Cremer & Kraka, 1985). However, in case of polysubstituted CP simple models do not always work. For example, in the systematic study of substituted CP, Jones and Schrumpf (Jones & Schrumpf, 1987a,b,c) showed that the bond distribution in the three-membered ring depends not solely on the electronic properties of substituents and their individual orientation, but also is strongly affected by stereochemistry of the whole molecule. According to their findings, in the case of a trans-conformation of (I), the asymmetry of the ring could be expected. Here we report the results of an X-ray structural study of compound (I) (Fig. 1 and Table 1).
Compound (I) has a trans-configuration of substituents in the central three-membered ring with one (at C3) at the opposite side of the ring plane from two others. The bond distribution in the central ring is highly asymmetric with a long bond C1—C2 [1.526 (2) Å] between two cis-oriented substituents, an intermediate bond [1.514 (2) Å] and a shorter one [1.504 (2) Å].
The conformations of the substituents are only slightly different. All of them adopt sg-configuration around the exo-cyclic C—C bonds, when one of the C—C bonds of the terminal ring is in s-cis-position relative to one of the bonds of the central ring. The conformation is described by torsion angles C2—C3—C10—C11, C3—C1—C4—C5 and C3—C2—C7—C8, which are -20.7, -13.5 and 3.1°, respectively. These similar conformations imply an equal extent of electronic interaction of each of the terminal CP rings with the central one and, indeed, all the CP—CP bonds are identical (mean 1.498 Å). However, it is the mutual orientation of substituents which induces the asymmetry of the central ring. The number of syn-periplanar (sp) C—C bonds of substituents is different for each of C—C bonds of the central cycle and, therefore, the effect of the substituents on each of them is different. There are two (sp)-orientated bonds for the shortest C2—C3 bond of the central ring, one for the intermediate C1—C3 bond and none for the longest C1—C2 one. This particular conformation of the cis-substituents is fixed by an intra-molecular hydrogen bond O1—H···O2 (Table 2).
The hydrogen bonds determine the packing of molecules in the crystal as well. Intermolecular hydrogen bonds O3—H···O1 and O2—H···O3 link molecules together in loose sheets perpendicular to (100) direction (Fig.2). These sheets form two types of interface: in the gap marked A in Fig.2 CP rings C10—C12 of the molecules of adjacent layers form contacting surfaces. In the gap of type B CP rings C4—C6 look toward each other. There are no strong intermolecular contacts between the sheets; however in the gap B there are contacts C6—H61···O1(2 - x, -1 - y, -z) [C···O 3.475 (2) Å], which are within the range of typical CH···O contacts formed by CH groups of three-membered rings (Allen et al., 1996). The shortest interlayer contacts in the gap B are H2···H112(1 - x, -1/2 + y, 1/2 - z) 2.56 (2) Å.