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Updated: Aug 14, 2026

Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides
Published on: May 26, 2019
Intramolecular [4 + 2] cycloaddition of nitroalkenes for construction of vicinal quaternary stereocenters
Scott E Denmark1, Ramil Y Baiazitov
1Roger Adams Laboratory, Department of Chemistry, University of Illinois, Urbana, Illinois 61801, USA. denmark@scs.uiuc.edu
Abstract:
[chemical reaction: see text]. Nitroalkene (E)-1 has been synthesized to test the feasibility of an intramolecular [4 + 2] cycloaddition in a planned synthesis of daphnilactone B. This nitro olefin contains two unique structural features, a nitromethylene lactone and a pendant diene, that combine under the action of SnCl4 in a highly selective fashion to afford nitronates 2a and 2b. These products represent the correct relationship for the vicinal quaternary stereogenic centers in the core of daphnilactone B.
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