1-Methyl, 1-(alkoxymethyl) and 1-(trimethylsilylmethyl) benzotriazoles are metallated at the α- carbon. Trapping of the resulting metallated species with chlorotrimethylsilane gives compounds which undergo Peterson olefination even with hindered ketones. In some cases, metallation at the 4-position of the benzotriazole is observed. An exhaustive metallation/silylation sequence gives 4-trimethylsilyl substituted 1-benzotriazoles in good ...