Amide-Enabled Distal and Multiple Dehydrogenative C-H Alkynylation with Tuning Site Selectivity
Bifu Liu1, Qiaoya Zhang2, Aidong Huang2
1School of Chemistry and Material Engineering, Huizhou University, Huizhou 516007, China.
Abstract:
Site-selective modification of complex functional molecules that contained diverse functionality held great challenges and synthetic promise. Herein, we developed amide-facilitated distal C-H alkynylation and dehydrogenation and multiple C-H alkynylation, switched by Ir(III) catalysis with a Ag(I) or Cu(II) oxidant. Switchable remote and dehydrogenative C-H alkynylation of drug actarit was achieved. Significantly, by exploration of directing priority and judicious amide directing groups, late-stage modification of celecoxib that bears strongly coordinating heterocycles with tunable site selectivity was also realized.
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