A general synthesis of 1-(1-alkenyl)benzotriazoles

Article abstract of DOI:10.1016/S0040-4020(99)00690-0

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 yields.