摘要:
Nitrile ylides, generated in basic conditions (HCI abstraction) from N-[tosylmethyl] and N-[diethoxyphosphorylmethyl] imino chlorosuifides, undergo 1,3-dipolar cycloadditions with electron-deficient dipolarophiles to produce pyrroles and pyrrolines. Heterogeneous media are found to furnish the best conditions for these reactions. One pyrrole can also be prepared from methyl N-[ethoxycarbonylmethyl] chiorothioimidate and dimethyl acetylenedicarboxylate on alumina-potassium fluoride mixture as solid support, under microwave irradiation.