Asymmetric Synthesis of α,α-Difluoro-β-amino Acid Derivatives from Enantiomerically Pure N-tert-Butylsulfinimines

• Published in: Journal of organic chemistry Vol. 67; no. 23; pp. 8276 - 8279
• Main Authors: Staas, Donnette D, Savage, Kelly L, Homnick, Carl F, Tsou, Nancy N, Ball, Richard G
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 15-11-2002
• Subjects: Aliphatic compounds; Amino Acids - chemical synthesis; Chemistry; Exact sciences and technology; Fluorine; Imines; Organic chemistry; Preparations and properties; Stereoisomerism; Sulfonamides - chemistry; Zinc Organic compounds; Reformatsky reaction; Sulfinamide; Imine; Stereoselectivity; Ester; Aminoester; Asymmetric synthesis; Aminoacid; Sulfoxide; Bromine Organic compounds; Fluorine Organic compounds; Chemical synthesis
• ISSN: 0022-3263; 1520-6904
• DOI: 10.1021/jo0259313

Addition of the Reformatsky reagent derived from ethyl bromodifluoroacetate to alkyl- and aryl-substituted N-tert-butylsulfinimines furnishes β-tert-butylsulfinamyl-β-substituted α,α-difluoroproponiates in diastereomeric ratios ranging from 80:20 to 95:5. The diastereomers are easily separated and the enantiomerically pure, protected β-amino esters are readily transformed to the corresponding acid, amide, and amine derivatives as useful synthons for medicinal chemistry targets.