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Several β-sulfoxy-substituted acetylenic carbinols were prepared by the addition of thiyl radicals and oxygen to conjugated enynes. The products obtained are derived from thiyl radical attack at the olefinic bond to generate a propargylic radical. Capture of this radical by oxygen followed by hydrogen transfer from thiophenol gives a hydroperoxide intermediate, which undergoes oxygen transfer by both intra- and intermolecular pathways. The resultant β-phenylsulfinyl propargylic alcohols proved to be versatile intermediates for the preparation of several different classes of compounds. The [2,3]-sigmatropic sulfinate to sulfoxide rearrangement was found to give 1,4-bis(phenylsulfonyl)1,3-butadienes, α,β-unsaturated phenylsulfoxy ketones, and β-phenylsulfonyl α-allenic sulfoxides