Diels-Alder reaction of fulvenes with N-(3,5-dichlorophenyl)-maleimide
摘要:
N-(3,5-Dichlorophenyl)-maleimide reacts smoothly with a variety of substituted fulvenes (1) to give only endo adducts (3) independent of the nature of fulvene substituent, Lewis acid catalyst, and reaction solvent and temperature. The structure of the Diets-Alder adduct 3f was determined by X-ray crystallography. Semi-empirical quantum methods (AM1) were used to rationalize the endo stereoselectivity.