Carbene‐Catalyzed Activation of C−Si Bonds for Chemo‐ and Enantioselective Cross Brook–Benzoin Reaction. (8th July 2022)

• Record Type: Journal Article
• Authors: Tang, Chenghao; Wang, Wei; Luo, Guoyong; Song, Chaoyang; Bao, Zhaowei; Li, Pei; Hao, Gefei; Chi, Yonggui Robin; Jin, Zhichao
• Is Part Of: Angewandte Chemie. Volume 134:Number 34(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-07-08
• Subjects: Acylsilanes -- Benzoin Condensation -- Brook Rearrangement -- Chemoselectivity -- N-Heterocyclic Carbenes; Chemistry -- Periodicals; 540
• DOI: 10.1002/ange.202206961
• Languages: English
• ISSNs: 0044-8249

Abstract

Abstract: The first carbene‐catalyzed asymmetric chemoselective cross silyl benzoin (Brook–Benzoin) reaction has been developed. Key steps of this reaction involve activation of the carbon–silicon bond of an acylsilane by a chiral N‐heterocyclic carbene (NHC) catalyst to form a silyl acyl anion intermediate. These acyl anions then undergo an addition reaction with indole aldehydes in a highly chemo‐ and enantioselective manner to afford α‐silyloxy ketones with excellent optical purities. The reaction mechanism of this cross Brook–Benzoin reaction was investigated through both experimental and computational methods. The chiral α‐hydroxy ketone derivatives obtained by this approach show promising, agrochemically interesting activity against harmful plant bacteria. Abstract : The first N‐heterocyclic carbene (NHC) catalyzed chemo‐ and enantioselective Brook–Benzoin reaction is disclosed. This reaction proceeds via silyl acyl anion intermediates and enables the synthesis of α‐silyloxy ketones bearing a wide range of functional groups in good to excellent yields and enantioselectivities.