Synthesis of Functionalized Coumarins and Quinolinones by NHC-Catalyzed Annulation of Modified Enals with Heterocyclic C–H Acids

• Published in: Journal of organic chemistry Vol. 79; no. 9; pp. 4245 - 4251
• Main Authors: Yetra, Santhivardhana Reddy, Roy, Tony, Bhunia, Anup, Porwal, Digvijay, Biju, Akkattu T
• Format: Journal Article
• Language: English
• Published: WASHINGTON American Chemical Society 02.05.2014; Amer Chemical Soc
• Subjects: acids; Acids - chemistry; carbenes; Catalysis; catalytic activity; chemical reactions; chemical structure; Chemistry; Chemistry, Organic; coumarins; Coumarins - chemical synthesis; Coumarins - chemistry; enantioselectivity; Heterocyclic Compounds - chemistry; Methane - analogs & derivatives; Methane - chemistry; Molecular Structure; organic chemistry; Physical Sciences; quinolones; Quinolones - chemical synthesis; Quinolones - chemistry; Science & Technology; ENANTIOSELECTIVE SYNTHESIS; 1,3-DICARBONYL COMPOUNDS; ALPHA,BETA-UNSATURATED ALDEHYDES; TRANSESTERIFICATION REACTIONS; ESTERS; EFFICIENT SYNTHESIS; ACYL AZOLIUMS; DERIVATIVES; MICHAEL ADDITION; CARBENE CATALYSIS

N-Heterocyclic carbene (NHC) catalyzed lactonization and lactamization of 2-bromoenals with heterocyclic C–H acids proceeding via the α,β-unsaturated acyl azolium intermediates is reported. The reaction furnished coumarin- or quinolinone-fused lactone/lactam derivatives. In addition, results of the...