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An efficient route to 4-aryl-5-pyrimidinylimidazoles via sequential functionalization of 2,4-dichloropyrimidine
Xiaohu Deng1, Neelakandha S Mani
1Johnson & Johnson Pharmaceutical Research & Development, LLC, San Diego, California 92121, USA.
Abstract:
[reaction: see text] Starting from 2,4-dichloropyrimidine, a concise synthetic route to medicinally important 4-aryl-5-pyrimidinylimidazoles is described. Sequential substitution of the 4- and 2-chloro groups using a regioselective Sonogashira coupling, followed by nucleophilic substitution, led to pyrimidinylalkyne derivatives, which were then oxidized to their corresponding 1,2-diketones. These 1,2-diketones, on cyclocondensation with ammonium acetate and an aldehyde, furnished the desired pyrimidinyl imidazoles in good overall yields.
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