N-Thiocyanatosaccharin: A “Sweet” Electrophilic Thiocyanation Reagent and the Synthetic Applications

摘要

N -Thiocyanatosaccharin ( R _( 1 )) was readily prepared from the sweet additive Saccharin in two steps with a 71% overall yield. By applying this new reagent to diverse nucleophiles such as benzothiophenes, indoles, oxindoles, aromatic amines, phenols, β-keto carbonyl compounds, and aromatic ketones, a novel electrophilic thiocyanation reaction was achieved with high yields (up to 99%). The potential recycling of Saccharin, the wide scope of substrates, and the mild reaction conditions made this protocol much more practical.