Diastereoselective construction of tetracyclic chromanes via a triply annulative strategy
Zhishun Tang1, Linghong Chen1, Pengxuan Yin1
1Key Laboratory of General Chemistry of the National Ethnic Affairs Commission, Key Laboratory of Pollution Control Chemistry and Environmental Functional Materials for Qinghai-Tibet Plateau of the National Ethnic Affairs Commission, School of Chemistry and Environment, Southwest Minzu University, Chengdu 610041, China. lixuefeng@swun.edu.cn.
Abstract:
A triple Michael/aldol cascade reaction has been established to construct tetracyclic chromanes in a diastereoselective fashion (≥5 : 1 dr). The polycyclic products were generated in 50-78% isolated yields under mild and metal-free conditions. Five reactive sites of enolate-tethered divinyl ketones were sequentially utilized to form four C-C bonds in a one-pot operation, leading to a construction of three new rings. Up to six consecutive stereocenters, including two quarternary stereogenic centers, were created in this domino process.
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