Enantioselective Synthesis of 3-Alkyl-1,5-Functionalized 1,4-Diynes via Isoxazol-5(4H)-ones
Ricardo Torán1, Sergi Vercher1, Pablo López1
1Departament de Química Orgànica, Facultat de Química, Universitat de València, C. Dr. Moliner 50, 46100 Burjassot, Spain.
Abstract:
An enantioselective strategy for the synthesis of chiral 3-alkyl-1,5-functionalized 1,4-diynes is reported. The method involves a highly enantioselective organocatalytic conjugate addition of isoxazol-5(4H)-ones to nitroenynes followed by a Zard-type transformation under one-pot conditions yielding chiral skipped diynes in good overall yields and with excellent enantioselectivities. This study highlights the synthetic versatility of the isoxazol-5(4H)-one scaffold and its value as a platform for accessing structurally diverse and synthetically relevant building blocks.
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