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Updated: Nov 10, 2025
Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Cobalt-Catalyzed (E)-β-Selective Hydrogermylation of Terminal Alkynes
Maxim R Radzhabov1, Neal P Mankad1
1Department of Chemistry, University of Illinois at Chicago, 845 W. Taylor St., Chicago, Illinois 60607, United States.
Abstract:
A cobalt-catalyzed method for the hydrogermylation of alkynes is reported, providing a selective and accessible route to (E)-β-vinyl(trialkyl)germanes from terminal alkynes and HGeBu3. As shown in multiple examples, the developed method demonstrates a broad functional group tolerance an practical utility for late-stage hydrogermylation of natural products. The method is compatible with alkynes bearing both aryl and alkyl substituents, providing unrivaled selectivity for previously challenging 1° alkyl-substituted alkynes. Moreover, the catalyst used in this method, Co2(CO)8, is a cheap and commercially available reagent. Conducted mechanistic studies supported the syn-addition of Bu3GeH to an alkyne π-complex.
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