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Updated: Aug 24, 2026

Synthesis of a Borylated Ibuprofen Derivative Through Suzuki Cross-Coupling and Alkene Boracarboxylation Reactions
Published on: November 30, 2022
An efficient asymmetric synthesis of an estrogen receptor modulator by sulfoxide-directed borane reduction
Zhiguo J Song1, Anthony O King, Marjorie S Waters
1Department of Process Research, Merck Research Laboratories, P.O. Box 2000, Rahway, NJ 07065, USA. zhiguo_song@merck.com
Abstract:
An efficient asymmetric synthesis of a selective estrogen receptor modulator (SERM) that has a dihydrobenzoxathiin core structure bearing two stereogenic centers is reported. The stereogenic centers were established by an unprecedented chiral sulfoxide-directed stereospecific reduction of an alpha,beta-unsaturated sulfoxide to the saturated sulfide in one step. Studies to elucidate the mechanism for this reduction are reported. Highly efficient Cu(I)-mediated ether formation was used to install the ether side chain, and selective debenzylation conditions were developed to remove the benzyl protecting groups on the phenols.
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