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Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Rh(III)-Catalyzed Strain-Release-Enabled C-H Alkenylation/[4+1] Annulation of Benzamides with Alkylidenecyclobutanes
Xin-Xing Liu1, Yuan-Jie Meng1, Zi-Feng Yang1
1Center for Drug Research and Development, Guangdong Pharmaceutical University, Guangzhou, 510006, P. R. China.
Abstract:
A Rh(III)-catalyzed strain-release-enabled C-H alkenylation/[4+1] annulation of benzamides with alkylidenecyclobutanes is described, enabling the efficient construction of 3-methyleneisoindolin-1-one derivatives. This protocol uniquely integrates Rh(III)-catalyzed C-H activation with strain-release ring-opening of alkylidenecyclobutanes, representing a rare example in which alkylidenecyclobutanes serve as C1 synthons in [4+1] annulation. Moreover, by subtly modifying the reaction conditions, Rh(III)-catalyzed C-H alkenylation was also achieved. This strategy features broad substrate scope and holds promise for late-stage functionalization of pharmaceutically relevant scaffolds. Its synthetic utility is further highlighted by scaled-up experiments and diverse downstream transformations.
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