The synthesis of novel pyrrolizidines under classical, ionic liquid and solvent-free microwave-assisted conditions

Novel pyrrolizidines (1) were synthesised from 1, 3-dipolar cycloaddition of azomethine ylides and dipolarophiles (4). The one-pot three-component reactions were highly diastereoselective and regioselective and were carried out in classical, room temperature ionic liquid and solvent-free microwave-assisted conditions. All methods gave the products in high yields, and their structures were determined by H-1 and C-13 NMR spectral data and X-ray diffraction.