LaCl3.7H20: An efficient catalyst for one-pot multi-component synthesis of 1,4-polyhydroquinoline derivatives through unsymmetrical Hantzsch reaction

An efficient one pot multi component synthesis of 1, 4-Polyhydroquinoline derivatives through unsymmetrical Hantzsch reaction using lanthanum chloride heptahydrate (LaCl3.7H2O) from an aromatic aldehyde, ethyl acetoacetate, dimedone and ammonium acetate as a nitrogen precursor in ethanol at room temperature is described. In the present work we report lanthanum chloride heptahydrate remarkably non-toxic in nature and ease of handling we explored the utility of lanthanum chloride as a catalyst for the synthesis of 1, 4-polyhydroquinoline derivatives. We newly report p-N, N-dimethylamino-cinnamaldehyde and m-chlorobenzaldehyde for the synthesis of 1, 4-Polyhydroquinoline derivatives through unsymmetrical Hantzsch reaction and was characterized by IR and 1HNMR spectroscopic methods.