Organocatalytic highly enantioselective tandem Michael–Knoevenagel reaction for the synthesis of substituted thiochromanes

✍ Scribed by Rajasekhar Dodda; Tanmay Mandal; Cong-Gui Zhao

• Book ID: 104095036
• Publisher: Elsevier Science
• Year: 2008
• Tongue: French
• Weight: 126 KB
• Volume: 49
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/j.tetlet.2008.01.113

✦ Synopsis

Enantioenriched tetrasubstituted thiochromanes have been synthesized using a tandem Michael addition-Knoevenagel reaction between 2-mercaptobenzaldehydes and benzylidenemalonates with a 9-epi-aminoquinine thiourea derivative as the catalyst. Steric and electron effects were found to affect profoundly the enantioselectivity and diastereoselectivity of the reaction.