Iridium-Catalyzed Sequential Silylation and Borylation of Heteroarenes Based on Regioselective C−H Bond Activation
作者:Masahito Murai、Naoki Nishinaka、Kazuhiko Takai
DOI:10.1002/anie.201801229
日期:2018.5.14
An iridium‐catalyzed regioselective sequential silylation and borylation of heteroarenes was developed, which represents a rare example of unsymmetrical intermolecular C−H bond difunctionalization through the introduction of two different functionalities during a one‐pot transformation. Although the substrate scope for the dehydrogenative silylation of heteroarenes has been limited mainly to electron‐rich
A pincer Ru(II) catalyst for the highly efficient undirected silylation of O- and S-heteroarenes with (TMSO)(2)MeSiH and Et3SiH is described, producing heteroarylsilanes with exclusive C2-regioselectivity, good functional group tolerance, and high turnover numbers (up to 1960). The synthetic utility of the silylated products is demonstrated by Pd-catalyzed Hiyama-Denmark cross-coupling under mild conditions. One-pot, two-step silylation and coupling procedures have been also developed.