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Highly enantioselective Biginelli reaction catalyzed by SPINOL-phosphoric acids
Fangxi Xu1, Dan Huang, Xufeng Lin
1Department of Chemistry, Zhejiang University, Hangzhou 310027, China.
Abstract:
A highly enantioselective Biginelli reaction promoted by chiral spirocyclic SPINOL-phosphoric acids has been developed. Under the optimized conditions with 5 mol% catalyst loading, a wide range of optically active dihydropyrimidinethiones (DHPMs) were obtained in high yields (up to 98%) with good to excellent enantioselectivities (up to 99% ee). The synthetic utility of this method was demonstrated by the synthesis of chiral precursors of three drugs, including (S)-Monastrol, (S)-L-771688 and (S)-SQ 32926.
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