Chemical transformations of diazoles in the reactions of carboxylation, N-siloxycarbonylation, and transsilylation

The behavior of 3,5-dimethylpyrazole, 3(5)-methylpyrazole, imidazole and their trimethyl-silyl derivatives in carboxylation, N-siloxycarbonylation, and transsilylation reactions was studied. A new Nsiloxycarbonylation reagent, diazole trimethylsilyl derivative-carbon dioxide, was found. This reagent makes it possible to obtain easily O-silylurethanes starting from primary, secondary amines and hydrazine derivatives, as well as to develop a convenient one pot synthesis method for trimethylsiloxycarbonyldiazoles.