Stable, crystalline α-(benzotriazolyl) methyl phenyl thioethers (1), easily prepared from carbonyl compounds, thiophenol and benzotriazole, are convenient reagents for the phenylthiomethylation of trimethylsilyl cyanide, trimethylallylsilane, and trimethylsilyl enol ethers to afford the corresponding substituted thioethers and β-phenylthioalkylketones (3) in good yields.