Tunable regiodivergent C-H alkenylation of 2-arylthiazoles via catalyst control
Guibin Wan1, Cheng Wang1, Pengfei Zhou1
1Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology, School of Chemistry and Chemical Engineering, Guangxi University, Nanning, Guangxi 530004, China. zhuan.zhang@gxu.edu.cn.
Abstract:
We have developed a novel and efficient Pd(II)- and Ru(II)-catalyzed switchable C-H alkenylation of 2-arylthiazoles with alkenes, achieving high levels of regio- and stereoselectivity. This protocol enables the selective synthesis of either C5- or ortho-alkenylated products, depending on the choice of metal catalyst. The reactions involve two distinct pathways: ortho-alkenylation proceeds via chelation-assisted ruthenation, while C5-alkenylation occurs through electrophilic palladation. This regiodivergent strategy offers a versatile approach for the direct construction of π-extended 2-arylthiazole derivatives, which show promising potential for applications in medicinal chemistry and materials science.
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