CRYSTAL AND MOLECULAR-STRUCTURE OF 4-DIHYDROXY-2,4-DIMETHYLCYCLOHEXANE-TRANS-1-ACETIC AND 4-DIHYDROXY-2,4-DIMETHYLCYCLOHEXANE-TRANS-1-ACETIC ACID GAMMA-LACTONE

During the transformation process of limonene to tetrahydrofuran deriv atives, the title compounds (+/-)-(4) have been obtained as crystallin e products and subjected to X-ray analysis. The crystals of trans-(4) ave orthorhombic, space group P2(1)2(1)2(1), with the lattice constant s a = 7.0445(5) Angstrom, b = 10.0908(4) Angstrom c = 14.0309(6) Angst rom; the absolute configuration at atoms C1, C2, and C4 is R(c1), S-c2 , and R(c4), respectively. The isomeric form cis-(4) crystallizes in t he monoclinic system, space group P2(1), with the following unit-cell parameters: a = 10.8275(4) Angstrom, b = 8.6994(5) Angstrom, c = 16.47 22(6) Angstrom, beta = 106.515(3)degrees. The asymmetric part of the u nit cell of cis-(4) contains three independent molecules. Each of thes e three molecules has the identical absolute configuration at all cent ers of chirality: S-c1, S-c2, and R(c4). (C) 1996 John Wiley & Sons, I nc.