Oxidative Dehydrosulfurative Cross-Coupling of 3,4-Dihydropyrimidine-2-thiones with Alkynes for Access to
Ngoc Son Le Pham1, Hyunik Shin2, Jun Yong Kang3
1Department of Chemistry, Chungnam National University, Daejeon 34134, Republic of Korea.
Abstract:
A reaction method is described for the one-step synthesis of 2-alkynylpyrimidines from 3,4-dihydropyrimidin-1H-2-thiones (DHPMs) via dehydrosulfurative Sonogashira cross-coupling with concomitant oxidative dehydrogenation using a Pd/Cu catalytic system. Together with the ready availability of DHPMs possessing various substituents at the C4-C6 positions, this transformation offers rapid and general access to diverse 2-alkynylpyrimidine derivatives.
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