Chiral Phosphoric Acid‐Catalyzed Enantioselective Synthesis of Pyrazole‐Based Unnatural α‐Amino Acid Derivatives. Issue 2 (28th October 2021)

• Record Type: Journal Article
• Authors: Woldegiorgis, Alemayehu Gashaw; Han, Zhao; Lin, Xufeng
• Is Part Of: Advanced synthesis & catalysis. Volume 364:Issue 2(2022)
• Page Start: 274
• Page End: 280
• Publication Date: 2021-10-28
• Subjects: Chiral phosphoric acids -- Unnatural amino acids -- Enantioselectivity -- Pyrazole -- Lactam; Catalysis -- Periodicals; Organic compounds -- Synthesis -- Periodicals; Chemistry -- Periodicals; Chemistry, Technical -- Periodicals; Chemistry -- Periodicals; Catalysis -- Periodicals; Technology, Pharmaceutical -- Periodicals; 547.2
• DOI: 10.1002/adsc.202101011
• Languages: English
• ISSNs: 1615-4150

Abstract

Abstract: An enantioselective synthesis of unnatural pyrazole‐based α‐chiral amino acid derivatives from the asymmetric reaction of N ‐aryl‐5‐aminopyrazoles with β, γ‐alkynyl‐α‐imino esters using a chiral spirocyclic phosphoric acid catalyst was developed. Using the established methodology, various pyrazole‐based α‐amino acid derivatives with tetrasubstituted carbon stereocenters were obtained in 67–98% yields and with 73–99% enantioselectivities. The NH2 functionality in the corresponding products enables further transformations to a chiral thiourea and a lactam. Abstract :