A variety of 2-monosubstituted and 2,2-disubstituted 1-chlorovinyl p-tolyl sulfoxides was synthesized through a one-pot procedure by the Horner-Wadsworth-Emmons reaction of carbonyl compounds with [chloro(diethoxyphosphoryl)(p-tolylsulfinyl)methyl]lithium, which was generated from diethyl chlorophosphate, chloromethyl p-tolyl sulfoxide, and lithium diisopropylamide in advance. The in situ-prepared sulfoxides were directly converted into alkynes via the sulfoxide/magnesium exchange reaction with i-PrMgCl and the subsequent Fritsch-Buttenberg-Wiechell rearrangement of the resulting magnesium alkylidene carbenoids.