Studies on the formation of a tricyclic C2-symmetric sulfide

Attempts to synthesise chiral sulfide 1 from the dimesylate precursor 5, via a cyclisation reaction using sodium sulfide in dimethyl sulfoxide, led to the unexpected formation of an unsymmetrical furan derivative 8. Studies were made into the effect of changing the leaving group, and changing the solvent of reaction. The desired compound could be synthesised in good yields from the xanthate 9 using a radical-mediated procedure.