Nitrilimine cycloadditions to MeOPEG-bounded alkenyl dipolarophiles
作者:Luisa Garanti、Giorgio Molteni、Pietro Casati
DOI:10.1039/b206629g
日期:2002.11.13
Base treatment of hydrazonoyl chloride 2 with MeOPEG-supported acrylates 1 and acrylamides 5 gave the corresponding MeOPEG-supported 4,5-dihydropyrazoles 3 and 6. Basic hydrolysis of the cycloadducts caused the removal of the MeOPEG pendant giving 5-carboxy- or 5-aminocarbonyl-4,5-dihydropyrazoles 7 and 8, respectively. Cycloaddition between 2 and enantiopure MeOPEG-supported acrylamide 10 gave a mixture of MeOPEG-supported cycloadducts 11 and 12 with low diastereoselectivity.