Some transition metal chelates of two ligands L1 and L2 were prepared and characterized by elemental analysis. The IR and 1H NMR spectra of several chelates of two ligands L1 and L2 showed the involvement of the azo g...Some transition metal chelates of two ligands L1 and L2 were prepared and characterized by elemental analysis. The IR and 1H NMR spectra of several chelates of two ligands L1 and L2 showed the involvement of the azo group in chelation with the transition metaI ions, in most of the studied chelates, and that the two ligands L1 and L2 showed the involvement of the azo group in chelation with the transition metal ions, in most of the studied chelates, and that the two ligands L1 and L2 were coordinated either in the enol or the keto form. IR spetra also showed that Fe(III)-, Ni(II)-, Mn(II)-, VO(II)-L1 and Cu(II)-L2 chelates behaved in a bidentate manner, in contrast with the two (1:1) M:L cobalt chelates with the two ligands are tridentate.TG analysis indicated the presence of three to twelve water molecules of hydration eliminated on heating up to 150℃ and one or two coordinated water molecules removed at 150~180℃.The octahedral structure is proposed fOr all the chelates, except Cu(II)-L2 and Ni(II)-L1 chelates which have square planar geometry, based on their electronic spectra展开更多
An efficient route for the synthesis of 5-（arylpropenylidine）-2,4,6-pyrimidinetrione 3 from an appropriate α,βunsaturated aromatic aldehydes 1 and barbituric acid 2 under both non-catalytic and solvent-free microw...An efficient route for the synthesis of 5-（arylpropenylidine）-2,4,6-pyrimidinetrione 3 from an appropriate α,βunsaturated aromatic aldehydes 1 and barbituric acid 2 under both non-catalytic and solvent-free microwave irradiation conditions was described. In this way, a range of biologically important compounds 3 was obtained in good to excellent yields （86-98%） in a very short reaction time （30-80 s）.展开更多
The knoevenagel condensation reaction of barbituric acid and aromatic aldehyde under ground and heated in solventless system was described. The reaction mechanism was also proposed. The structures of the products were...The knoevenagel condensation reaction of barbituric acid and aromatic aldehyde under ground and heated in solventless system was described. The reaction mechanism was also proposed. The structures of the products were identified by IR, 1H NMR, 13 C NMR and UV. 5 Alkylidene barbituric acid was the only product in the two reaction systems.展开更多
Knovenagel reaction of barbituric acid with different aldehydes were used to synthesize new barbiturates. This is a novel method which can be used to synthsis various types of new generation of barbiturates which are ...Knovenagel reaction of barbituric acid with different aldehydes were used to synthesize new barbiturates. This is a novel method which can be used to synthsis various types of new generation of barbiturates which are different from the previously reported.展开更多
Agreen regioselective synthesis of some new and known 9-aryl-5,9-dihydropyrimido[4,5-d][l,2,4]triazolo[1,5-a]pyrimidine-6,8（4H,7H）-diones has been described via the microwave-assisted one-pot reaction of 3-amino-1H-...Agreen regioselective synthesis of some new and known 9-aryl-5,9-dihydropyrimido[4,5-d][l,2,4]triazolo[1,5-a]pyrimidine-6,8（4H,7H）-diones has been described via the microwave-assisted one-pot reaction of 3-amino-1H-1,2,4-triazoles,aromatic aldehydes and barbituric acids under solvent- and catalyst-free conditions.This operationally simple procedure is less laborious and provides a better scope than previously reported procedures.展开更多
文摘Some transition metal chelates of two ligands L1 and L2 were prepared and characterized by elemental analysis. The IR and 1H NMR spectra of several chelates of two ligands L1 and L2 showed the involvement of the azo group in chelation with the transition metaI ions, in most of the studied chelates, and that the two ligands L1 and L2 showed the involvement of the azo group in chelation with the transition metal ions, in most of the studied chelates, and that the two ligands L1 and L2 were coordinated either in the enol or the keto form. IR spetra also showed that Fe(III)-, Ni(II)-, Mn(II)-, VO(II)-L1 and Cu(II)-L2 chelates behaved in a bidentate manner, in contrast with the two (1:1) M:L cobalt chelates with the two ligands are tridentate.TG analysis indicated the presence of three to twelve water molecules of hydration eliminated on heating up to 150℃ and one or two coordinated water molecules removed at 150~180℃.The octahedral structure is proposed fOr all the chelates, except Cu(II)-L2 and Ni(II)-L1 chelates which have square planar geometry, based on their electronic spectra
文摘An efficient route for the synthesis of 5-（arylpropenylidine）-2,4,6-pyrimidinetrione 3 from an appropriate α,βunsaturated aromatic aldehydes 1 and barbituric acid 2 under both non-catalytic and solvent-free microwave irradiation conditions was described. In this way, a range of biologically important compounds 3 was obtained in good to excellent yields （86-98%） in a very short reaction time （30-80 s）.
文摘The knoevenagel condensation reaction of barbituric acid and aromatic aldehyde under ground and heated in solventless system was described. The reaction mechanism was also proposed. The structures of the products were identified by IR, 1H NMR, 13 C NMR and UV. 5 Alkylidene barbituric acid was the only product in the two reaction systems.
文摘Knovenagel reaction of barbituric acid with different aldehydes were used to synthesize new barbiturates. This is a novel method which can be used to synthsis various types of new generation of barbiturates which are different from the previously reported.
文摘Agreen regioselective synthesis of some new and known 9-aryl-5,9-dihydropyrimido[4,5-d][l,2,4]triazolo[1,5-a]pyrimidine-6,8（4H,7H）-diones has been described via the microwave-assisted one-pot reaction of 3-amino-1H-1,2,4-triazoles,aromatic aldehydes and barbituric acids under solvent- and catalyst-free conditions.This operationally simple procedure is less laborious and provides a better scope than previously reported procedures.
