Rapid and General Amination of Aryl Boronic Acids and Esters Using O-(Diphenylphosphinyl)hydroxylamine (DPPH)
Matthew G Kung1, Polpum Onnuch1, Richard Y Liu1
1Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States.
Abstract:
O-(Diphenylphosphinyl)hydroxylamine (DPPH) is a general reagent for the conversion of (hetero)aryl boronic acids and esters to primary anilines. The transformation proceeds rapidly at rt and exhibits a broad substrate scope and exceptional functional-group tolerance. In terms of rate, the reaction is relatively insensitive to the electronic properties of the substrate, in contrast to similar reactions using electrophilic amination reagents such as hydroxylamine-O-sulfonic acid. Consequently, this protocol is particularly useful for accessing electron-deficient (hetero)aryl anilines, which had been challenging to prepare using prior methods.
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