Rapid amide ligation between α-halo acylsilanes and amines under aqueous conditions
Wenzhang Xiong1, Wentao Zhu1, Jiyan Pang2
1School of Chemistry, Sun Yat-sen University, Guangzhou, China.
Abstract:
Amide functional group is useful in all branches of molecule-based science. Hundreds of amide synthetic protocols have been invented over the history of organic chemistry either through developing new coupling reagents or engineering non-traditional coupling partners. However, the click-type amide ligation that operates under biocompatible conditions with high chemoselectivity and rapid kinetics is rare. Herein we report that native amines react with α-halo acylsilanes to afford amides selectively with rapid kinetics. Enabled by a tandem silyl-migration/desilylation process, this amide ligation tolerates a wide range of unprotected polar functional groups and proceeds even at diluted concentrations. Beyond the synthesis of simple amides and peptides in both solution and solid phase, it is also applicable to selective functionalization of complex natural products, protein bioconjugation and synthesis of non-conventional functional polyamides under mild conditions.
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