DABCO-Catalyzed Reaction of Allenic Esters and Ketones with Salicyl N-Tosylimines:  Synthesis of Highly Functionalized Chromenes

2005-07-07T00:00:00Z (GMT) by Yong-Ling Shi Min Shi
DABCO-catalyzed reactions of salicyl N-tosylimines with ethyl 2,3-butadienoate and penta-3,4-dien-2-one proceed smoothly at room temperature in dichloromethane to give the corresponding chromenes in good to excellent yields.