N,O bis(alkylsilyl)carbamates, new silylating agents for the preparation of chemically bonded stationary phases

N, O bis(alkylsilyl)carbamates are convenient silylating agents for the preparation of alkyl bonded phase useful in HPLC. These derivatives, prepared from alkylchlorosilanes and ammonium carbamate, result in, a more activesilylation than the corresponding chlorosilanes. The side products, ammonia and carbon dioxide, released by the reaction are easly removed and a practically complete silylation is achieved.