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1‐(Trimethylsilylmethyl)benzotriazole is readily prepared from benzotriazole and chloromethyltrimethylsilane. It undergoes fluoride‐catalyzed desilylation with carbonyl compounds and forms an anion that can be alkylated and acylated readily and undergoes Peterson olefination. 1‐(Cyclohexylidenemethyl)benzotriazole is lithiated exclusively at the α carbon atom, and the anion can be cleanly alkylated. 1‐(α‐Acylalkyl)benzotriazoles are reduced to ketones with zinc and acid. The stability of 1‐alkenylbenzotriazoles to hydrolysis has been studied.

Phenols and naphthols are benzotriazolylmethylated by 1‐(hydroxymethyl)‐1H‐benzotriazole (13) (a formaldehyde derivative) in the o‐ or (if both o‐positions are occupied) in the p‐position. The reaction can be extended to other aldehydes in the case of the naphthols. The methylene group in the o‐(benzotriazolylmethyl)phenols can be lithiated (but only after trimethylsilyl protection of the hydroxy group) and then substituted by various electrophiles. The benzotriazole residues in both the primary products and in their substituted derivatives can be displaced by the alkyl anions of Grignard reagents or by hydride ions allowing the elaboration of many new types of substituted phenols.

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