| Biginelli reaction is the method for synthesis of 3,4-dihydropyrimidine-2?1H?-one/thione?DHPMs? by aldehyde, urea/thiourea and ?-dicarbonyl compound. DHPMs have wide spectra of biological activities, such as antitumor, anti-hpertensive, calcium channel blockers, mitotic kinesin Eg5 inhibitors, ?1a-adrenergic antagonists, anti-inflammatory properties, antiviral, et al. The dihydropyrimidine nucleus is important drug skeleton, several alkaloids with anti HIV virus activity contain the dihydropyrimidine nucleus. In this paper, we synthesize a new Bi-complex using BiCl3 and 6-hydroxypurine, and study its application in Biginelli reaction.Firstly, Two Bi-complexes[(C4H12N2)2[BiCl6]Cl·H2O and?C5H6N4O??C5H5N4O?3?C5H4N4O?[Bi2Cl11]Cl2 synthesized by volatilization, and single crystal structure was determined after characterization.Secondly,?C5H6N4O??C5H5N4O?3?C5H4N4O?[Bi2Cl11]Cl2 applied to 3,4-dihydropyri midine-2?1H?-one via Biginelli reaction, reaction occured in refluxing ethanol, and the catalyst could be recycled. We investigated the effect of the type of catalyst, solvent, et al., and determined the optimal reaction conditions. Synthesized a series of 3,4-dihydropyri midine-2?1H?-one compound, and all products were determined by MS and 1H NMR.Thirdly,?C5H6N4O??C5H5N4O?3?C5H4N4O?[Bi2Cl11]Cl2 applied to 3,4-dihydropyri midine-2?1H?-thione via Biginelli reaction with TfOH together, reaction occured in refluxing ethanol, and the catalyst could be recycled. We optimized reaction conditions based on the reaction conditions of synthesis of 3,4-dihydropyrimidine-2?1H?-one, TfOH was added as co-catalyst. Synthesized a series of 3,4-dihydropyrimidine-2?1H?-thione compound, and all products were determined by MS and 1H NMR. |
PDF Full Text Request