Reductive Cleavage of Aryl <i>O-</i>Carbamates to Phenols by the Schwartz Reagent. Expedient Link to the Directed <i>Ortho</i> Metalation Strategy
作者:Justin Morin、Yigang Zhao、Victor Snieckus
DOI:10.1021/ol401547d
日期:2013.8.16
efficient method for the reductive cleavage of aryl O-carbamates to phenols, 1 → 2 using the Schwartz reagent is reported. The method is selective, tolerating a large number of functional groups; may be carried out by direct or by an economical in situ procedure; and, notably, establishes a synthetic connection to the directedorthometalationstrategy (Figure 1) allowing new entries into difficult to
The directed ortho borylation of phenol derivatives protected with an N,N-diethylcarbamoyl group was efficiently catalyzed by an immobilized monophosphine-Ir system, which was prepared in situ from [Ir(OMe)(cod)](2) and a silica-supported, compact phosphine. The utility of the carbamoyloxy group as a leaving group for metal-catalyzed cross-coupling reactions was demonstrated by its utilization in the synthesis of a terphenyl derivative.