Convenient stereoselective synthesis of 3-hydroxy-2-iodo-2(E)-alkenyl sulfides via iodohydroxylation of 1,2-allenyl sulfoxides in the presence of BnSH

The iodohydroxylation of 1,2-allenyl sulfoxides with I2 in the presence of BnSH affords 3-hydroxy-2-iodo-2(E)-alkenyl sulfides in good yields and selectivities. The stereochemistry for the products of this transformation is opposite to what was obtained from the iodohydroxylation of 1,2-allenyl sulfides. Based on the results of some control experiment, a mechanism was proposed.