Orthogonal and Modular Arylation of Alkynylgermanes
Amit Dahiya, Franziska Schoenebeck
Abstract
While alkynyl silanes are ubiquitously employed in synthetic handles, especially in the build-up of more complex alkynes, such as alkyne-based polyaromatic materials, the identification of a similar robust functionality with ideally orthogonal reactivity space would greatly expand the modularity and scope in the construction of functional alkynes. We herein disclose the efficient, mild, and modular arylation of alkynylgermanes, which is enabled by blue light-assisted gold catalysis and allows for the chemoselective arylation of the alkynylgermane moiety at room temperature in 2 h over alkynyl silanes, aryl halides, aryl BPin, and various other functional groups. Conversely, the alkynylgermane proved to be uniquely stable toward typical alkynyl silane deprotection conditions as well as Sonogashira cross-coupling conditions, which underlines its orthogonal reactivity space and significant potential as a complementary robust alkyne handle.