Silver/ThioClickFerrophos-Catalyzed 1,3-Dipolar Cycloaddition and Tandem Addition–Elimination Reaction of Morita–Baylis–Hillman Adducts

• Published in: Journal of organic chemistry Vol. 86; no. 21; pp. 14586 - 14596
• Main Authors: Suzuki, Yuko, Kanemoto, Kazuya, Inoue, Ayana, Imae, Kazumi, Fukuzawa, Shin-ichi
• Format: Journal Article
• Language: English
• Published: WASHINGTON American Chemical Society 05.11.2021; Amer Chemical Soc
• Subjects: Catalysis; Chemistry; Chemistry, Organic; Cycloaddition Reaction; Esters; Physical Sciences; Science & Technology; Silver; Stereoisomerism; ZH SYSTEMS; ASYMMETRIC CONJUGATE ADDITION; ACTIVATED ALLYLIC ACETATES; AMINO-ACIDS; CONSTRUCTION; AZOMETHINE YLIDES; POTENTIAL 1,3-DIPOLES; GLUTAMIC-ACID DERIVATIVES; MICHAEL ADDITION; ALKALOIDS
• ISSN: 0022-3263; 1520-6904
• DOI: 10.1021/acs.joc.1c01440

The asymmetric 1,3-dipolar cycloaddition of glycine imino esters to Morita–Baylis–Hillman (MBH) adducts or acetylated MBH adducts is described. The reaction was efficiently catalyzed by AgOAc/(R,S p)-ThioClickFerrophos at room temperature to afford pyrrolidine derivatives bearing a quaternary carbon as a single diastereomer with excellent enantioselectivity. When a cyclic pyrroline ester was used as the nucleophile instead of a glycine imino ester, the enantioselective tandem addition–elimination reaction with an acetylated MBH adduct proceeded with an excellent yield and enantioselectivity, resulting in the formation of an exo-olefin. The wide substrate scope of these reactions and the transformability of the products enable expeditious access to divergent multifunctionalized pyrrolidines in an optically pure fashion.