Abstract
Benzotriazol-1-yl-sulfonyl azide, a new crystalline, stable, and easily available diazotransfer reagent provides N-(alpha-azidoacyl)benzotriazoles convenient for N-, O-, C- and S-acylations. The efficient syntheses of various amides, azido protected peptides, esters, ketones and thioesters is reported together with a wide range of azides (including alpha-azido acids from alpha- amino acids in partially aqueous conditions) and diazo compounds.