Optically active 2,3-epoxy sulfides as precursors to 3-hydroxy-1,2-dithioethers and 3-hydroxy-1-alkenylthioethers

Procedures are reported far the conversion of 2,3-epoxysulfides to 3-hydrox y-1,2-dithioethers. Conventional nucleophilic ring opening using a thiolate gives a mixture of products resulting from ring opening at C-2 and C-3, wi th the latter predominating. With sodium thiolates in DMF a competing beta- elimination process is observed to form 3-hydroxy-1-alkenylthioethers. Alte rnatively, Lewis acid induced thiiranium ion generation from a 2,3-epoxy su lfide, and nucleophilic ring opening with S-trimethylsilylthiophenol gives 3-hydroxy-1,2-dithioethers with full regio- and stereo-control. (C) 1999 El sevier Science Ltd. All rights reserved.