Clean three-step synthesis of 4,5-dihydro-1H-pyrazoles starting from alcohols using polymer supported reagents

Abstract

Nafion-TMS mediated Mukaiyama aldol reaction of silyl enol ethers with aldehydes, obtained from mild oxidation of alcohols with polymer supported perruthenate (PSP), yielded α,β-unsaturated ketones, which upon treatment with hydrazines allowed the clean synthesis of 4,5-dihydro-1H-pyrazoles.

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