A Practical Solution to Stereodefined Tetrasubstituted Olefins
Jianxin Dai, Minyan Wang, Guobi Chai, Chunling Fu and Shengming Ma*
*Laboratory of Molecular Recognition and Synthesis, Department of Chemistry, Zhejiang University, Hangzhou 310027, Zhejiang, People’s Republic of China, Email: masmsioc.ac.cn
J. Dai, N. Wang, G. Chai, C. Fu, S. Ma, J. Am. Chem. Soc., 2016, 138, 2532-2535.
DOI: 10.1021/jacs.6b00051 (free Supporting Information)
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Conjugate addition of organozinc reagents to readily available 2,3-allenals enables a unique and practical method for the preparation of stereodefined, fully substituted olefins bearing an extremely versatile aldehyde functionality. The geometry of the newly formed double bond is controlled by unique regiospecific oxygen-protonation of the enolate intermediates, generating 1,3-alkadienols, followed by 1,5-H-transfer.
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