Base-catalyzed regioselective C(sp3)-Si bond activation of silacyclobutanes and benzosilacyclobutenes
Yuanfang Kong1, Delong Mu2,3
1College of Pharmacy, Henan University of Chinese Medicine, Zhengzhou, Henan, 450046, China.
Abstract:
The development of a green, sustainable, and environment-friendly activation model is of great significance in catalytic chemistry. Herein, a transition-metal- and ligand-free, base-catalyzed regioselective C(sp3)-Si bond activation of silacyclobutanes (SCBs) and benzosilacyclobutenes (BSBs) has been developed. The protocol features a simple catalytic system that proceeds smoothly under air atmosphere without requiring inert gas protection. A variety of SCBs and BSBs are competent substrates, along with a range of nucleophiles as coupling partners. Furthermore, the strategy provides a straightforward platform for the late-stage functionalization of various bioactive molecules, enabling access to diverse quaternary silicon-containing scaffolds. Preliminary mechanistic investigations indicate that the C-Si bond cleavage is involved in the rate-determining step, and the hydrogen source originates from the nucleophile. In addition, the proposed mechanism is consistent with our experimental results and further supported by DFT calculations.
More Related Videos
19:58Palladium N-Heterocyclic Carbene Complexes: Synthesis from Benzimidazolium Salts and Catalytic Activity in Carbon-carbon Bond-forming Reactions
Published on: July 30, 2017
09:37Imine Metathesis by Silica-Supported Catalysts Using the Methodology of Surface Organometallic Chemistry
Published on: October 18, 2019
Related Concept Videos
Cycloaddition Reactions: Overview
Benzene to 1,4-Cyclohexadiene: Birch Reduction Mechanism
Cycloaddition Reactions: MO Requirements for Thermal Activation
Regioselectivity and Stereochemistry of Hydroboration
Hydroboration proceeds in a concerted fashion with the attack of borane on the π bond, giving a cyclic four-centered transition state. The –BH2 group is bonded to the less substituted carbon and –H to the more substituted carbon. The concerted nature requires the simultaneous addition of –H and –BH2 across the same face of the alkene giving syn stereochemistry.
Nucleophilic Aromatic Substitution: Elimination–Addition
Reduction of Benzene to Cyclohexane: Catalytic Hydrogenation
