Convenient method for the preparation of carbamates, carbonates, and thiocarbonates.

A convenient, rapid, and efficient method for the preparation of carbamates from amines with 1-alkoxycarbonyl-3-nitro-1,2,4-triazole transfer reagents is reported. Reactions of newly synthesized stable crystalline reagents with alkyl amines were completed in a few minutes without any additional base, and highly pure carbamates were obtained without chromatographic purification. These highly active reagents are also useful for the selective protection of nucleobases and preparation of carbonates and thiocarbonates.