Asymmetric Tandem Michael Addition-Wittig Reaction to Cyclohexenone Annulation
Yan-kai Liu, Chao Ma, Kun Jiang, Tian-Yu Liu and Ying-Chun Chen*
*Key Laboratory of Drug-Targeting and Drug Delivery System of Education Ministry, Department of Medicinal Chemistry, West China School of Pharmacy, Sichuan University, Chengdu 610041, China, Email: ycchenhuaxiyahoo.com.cn
Y.-k. Liu, C. Ma, K. Jian, T.-Y. Liu, Y.-C. Chen, Org. Lett., 2009, 11, 2848-2851.
DOI: 10.1021/ol9010568 (free Supporting Information)
A highly stereoselective tandem Michael addition-Wittig reaction of (3-carboxy-2-oxopropylidene)triphenylphosphorane and α,β-unsaturated aldehydes gives multifunctional 6-carboxycyclohex-2-en-1-ones in excellent diastereo- and enantioselectivities by employing the combined catalysis of a bulky chiral secondary amine, LiClO4, and DABCO.
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