Ligand-Enabled C-H Olefination and Lactonization of Benzoic Acids and Phenylacetic Acids via Palladium Catalyst
Yangyang Wang1, Xiaobo Xu1, Gaorong Wu1
1Engineering Research Centre of Pharmaceutical Process Chemistry, Ministry of Education, School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, P. R. China.
Abstract:
A novel ligand propan-2-one O-(p-tolylcarbamoyl) oxime (L7) has been developed to promote C(sp2)-H olefination of benzoic acids and phenylacetic acids via a palladium catalyst. With the subsequent lactonization of the olefinated products through 1,4-addition, highly monoselective cyclic lactone products of benzofuranones and benzopyrones were obtained in moderate to excellent yields. The DFT calculation demonstrated that the novel ligand propan-2-one O-(p-tolylcarbamoyl) oxime (L7) could improve the C-H activation reaction to give cyclic lactone products elegantly.
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