New precursors for preparing organic conducting materials: Synthesis of (R)-hydroxymethylbis(ethylenedithio)tetrathiafulvalene, and the ring expansion of a cyclic sulfate ester

The chiral hydroxymethyl-substituted derivative of bis(ethylenedithio)tetrathiafulvalene, has been synthesized from D-mannitol via the cyclic sulfate ester of (2R)-3-(2-methoxyethoxymethoxy)propane-1,2-diol. The latter substance slowly decomposes at 45°C and should be used when freshly prepared. In contrast, the cyclic sulfate ester of (2R)-3-benzoyloxypropane-1,2-diol containing a five-membered ring, undergoes clean rearrangement at room temperature to the cyclic sulfate ester of 2-benzoyloxypropane-1,3-diol, containing a six-membered ring.