N-(α-Lithioalkyl)tetrazoles and their Reactions with Electrophiles

Treatment of 1- and 2-alkyl-5-phenyltetrazoles with tert-butyllithium in tetrahydrofuran at -78 °C gives "dipole-stabilised" α-lithioalkyl derivatives which are readily converted into the corresponding deuterated, silylated, alkylated, hydroxymethylated, acylated and carboxylated derivatives, mostly in high yield. Lithiation of 5-phenyl-2-trimethylsilylmethyltetrazole followed by reaction with aldehydes results in Peterson olefination to give 2-alkenyltetrazoles in good yield.