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Updated: Jun 17, 2026

Efficient Construction of Drug-like Bispirocyclic Scaffolds Via Organocatalytic Cycloadditions of α-Imino γ-Lactones and Alkylidene Pyrazolones
Published on: February 7, 2019
Origin of stereoselectivity in the (4 + 3) cycloadditions of chiral alkoxy siloxyallyl cations with furan
Elizabeth H Krenske1, K N Houk, Michael Harmata
1Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, USA.
Abstract:
The mechanisms and stereoselectivities of (4 + 3) cycloadditions between chiral alkoxy siloxyallyl cations and furan are examined using density functional theory calculations. These cycloadditions are predicted to take place via stepwise mechanisms. The stereoselectivities of cycloadditions involving siloxyallyl cations derived from chiral alpha-methyl benzylic alcohols are controlled by two effects: minimization of steric repulsion between the alpha-Me group and the allyl group and attractive CH-pi interactions between the furan and the aryl group.
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