Pd-Catalyzed sequential hydroarylation and olefination reactions of 3-allylchromones.

Org Biomol Chem

National Research Institute of Chinese Medicine, Ministry of Health and Welfare, Taipei 11221, Taiwan, Republic of China.

Published: August 2019

In this paper, a novel approach to regioselective α- or γ-hydroarylation of 3-allylchromones with electron-rich arenes has been presented. Results of this study indicated that the regioselectivity was dependent on the substituent at the γ-position of the allyl group. Hydrogen or alkyl substitution favored α-hydroarylation, whereas aryl substitution favored γ-hydroarylation. This methodology provides an efficient means to achieve the α- or γ-selective hydroarylation of 3-allylchromones. Application of α-hydroarylation to perform Pd-catalyzed one-pot sequential α-hydroarylation and π-chelation-assisted olefination has also been reported.

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http://dx.doi.org/10.1039/c9ob01147aDOI Listing

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