122nd General Meeting of the KCS

Type Oral Presentation
Area Oral Presentations for Young Scholars in Organic Division
Room No. Room 325A+B
Time THU 09:00-:
Code ORGN.O-1
Subject Enantioselective Protonation/Nucleophilic Addition and Strecker Reaction Catalyzed by Chiral Oxazaborolidinium Ion
Authors Ki-Tae Kang , Do Hyun Ryu*
Department of Chemistry, Sungkyunkwan University, Korea
Abstract A new chiral Brønsted acid derived from carboxylic acid and a chiral oxazaborolidinium ion (COBI), as an activator, is introduced. This acid was successfully applied as a catalyst for the highly enantioselective protonation/nucleophilic addition of diazoesters with carboxylic acids. Meanwhile, In the presence of a catalytic amount of COBI, aldimine reacted with trimethylsilyl cyanide (TMSCN) to a afford α-aminonitriles in excellent yields and enantioselectivities. The three-component asymmetric process studied here significantly improves upon the original Strecker reaction, and has advantages over previous reactions using unstable imines. High levels of enantioselectivities in the synthesis of α-aminonitrile derivatives with wide substrate generality were obtained via these reactions. The reaction proceeded in good yields (up to 98%) with excellent enantioselectivities (up to 99% ee).
E-mail kkooru11@naver.com