A Powerful Chiral Super Brønsted C–H Acid for Asymmetric Catalysis

• Published in: Journal of the American Chemical Society Vol. 144; no. 7; pp. 2853 - 2860
• Main Authors: Peng, Bingfei, Ma, Jiguo, Guo, Jianhua, Gong, Yating, Wang, Ronghao, Zhang, Yi, Zeng, Jinlong, Chen, Wen-Wen, Ding, Kuiling, Zhao, Baoguo
• Format: Journal Article
• Language: English
• Published: WASHINGTON American Chemical Society 23.02.2022; Amer Chemical Soc
• Subjects: acidity; amination; catalytic activity; Chemistry; Chemistry, Multidisciplinary; enantioselectivity; Physical Sciences; protonation; Science & Technology; silyl enol ethers; ENANTIOSELECTIVE PROTONATION; PHOSPHORIC-ACID; DIELS-ALDER REACTION; 1,3-DIPOLAR CYCLOADDITION; CARBENE INSERTION; TRANSFER HYDROGENATION; CARBONYL-COMPOUNDS; ALLYLIC AMINATION; MUKAIYAMA-MANNICH REACTION; FRIEDEL-CRAFTS ALKYLATION
• ISSN: 0002-7863; 1520-5126; 1520-5126
• DOI: 10.1021/jacs.1c12723

A new type of chiral super Brønsted C–H acids, BINOL-derived phosphoryl bis­((trifluoro­methyl)­sulfonyl) methanes (BPTMs), were developed. As compared to widely utilized BINOL-derived chiral phosphoric acids (BPAs) and N-triflyl phosphoramides (NTPAs), BPTMs displayed much higher Brønsted acidity, resulting in dramatically improved activity and excellent enantioselectivity as demonstrated in catalytic asymmetric Mukaiyama–Mannich reaction, allylic amination, three-component coupling of allyltrimethylsilane with 9-fluorenylmethyl carbamate and aldehydes, and protonation of silyl enol ether. These new strong Brønsted C–H acids have provided a platform for expanding the chemistry of asymmetric Brønsted acid catalysis.