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Updated: Oct 20, 2025

Versatile CO2 Transformations into Complex Products: A One-pot Two-step Strategy
Published on: November 9, 2019
Carbon Monoxide Coupling Reactions via a Frustrated Lewis Pair-Derived η2-Formyl Borane
Qiu Sun1, Constantin G Daniliuc1, Klaus Bergander1
1Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 40, 48149 Münster, Germany.
Abstract:
The η2-formyl borane system 3 is readily available by carbonylation of the vicinal P/BH frustrated Lewis pair (FLP) 1. It serves as a frustrated C/B Lewis pair toward carbon dioxide or phenylisocyanate. In the presence of B(C6F5)3, it forms the coupling product between two CO-derived units. The resulting compound 13 rearranged to a doubly O-borylated endiolate, with both of the central carbon atoms originating from carbon monoxide. The subsequent treatment with a silane gave a rare macrocyclic silicon endiolate.
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