(4aR,8aS,9aR,10aS)-8a,9a-Difluoro-1,4,4a,5,8,8a,9,9a,10,10a-decahydroanthracene-4a,10a-diol hemihydrate

Abstract

The title compound, C(14)H(18)F(2)O(2)·0.5H(2)O, a hemihydrate of a C(s)-symmetric unsaturated difluorodiol, crystallizes in the centrosymmetric space group P2/m (Z = 4). The asymmetric unit contains two crystallographically independent difluorodiol half-molecules, occupying the mirror planes at (x, 0, z) and (x, 1/2, z), and half a molecule of water, lying on the twofold axis at (0, y, 0). Four difluorodiol molecules self-assemble around each solvent water molecule via O-H...O hydrogen bonds in a near tetrahedral symmetry to generate a cylindrical column-like architecture.

From Molecular to Supramolecular: An Exploration into the Modes of Self- assembly in Conformationally Locked Polycyclitols

“…[30] A synthetic route, similar to the one engendering 31 from the epoxide 34, led us to obtain the difluorodiol 32 and the difluorohexol 33 from the syn-diepoxide 36 (conveniently prepared, along with its anti-diastereomer 37, from 1,4,5,8,9,10-hexahydroanthracene [22,40] ) via the common intermediate 38. [36,41] Unlike the syn-diepoxide 36, which underwent bis-fluorination in pyridine poly(hydrogen fluoride) with complete regio-and streocontrol to furnish the unsaturated difluorohexol 38 as the sole product, [36] its sibling 37 afforded the tetracyclic monofluoroalcohol 39 (Fig. 13) as the major component of the product mixture via a tandem HF-mediated epoxide ring opening and transannular oxacyclization.…”