Synthesis?Characterization And The Catalytic Activity For Urea Hydrolysis Of Ni(?) Metal Complexes Of Salicyhydrazide Derivatives

Urease that contains nickel is a key oligomeric enzyme in the cycling process of nitrogen.Urease can catalyze urea to produce ammonia and carbon dioxide.It is often found in bacteria,fungi and plants.Urease can be used not only to provide the necessary nitrogen for the growth of the organism,but also to attend the transfer process of nitrogen.Besides,it can be as the defense proteins of ammonia toxicity as well.As the necessary trace element of people,nickel often appears in the activity center of urease.Therefore,how to utilize or inhibit urease activity is the research focus of urease and urease mimetic.Since the salicyhydrazide derivatives have a wide range of biological activity,which makes salicyhydrazide derivatives and its urease mimetic to be popular around the researchers.In this paper,three new salicyhydrazide derivatives are systhesized through introducing 3-benzoyl acrylic acid and ?-furoyl groups.The corresponding nickel-metal complexes are formed by self-assembly and their crystal structures were analyzed.Besides,the nickel-metal complexes obtained have been studied for their catalytic activity.The main research work is as follows:(1)Aluminum chloride was used as a catalyst which promoted the reaction of benzene and maleic anhydride to get the compound 3-benzoyl acrylic acid.The 3-benzoyl acrylic acid reacted further to systhesize its acyl chloride.The acyl chloride obtained is reacted with salicyhydrazide to get the ligand N-(3-benzoyl acryloyl)salicyhydrazide.The compound was characterized by IR,1H NMR,13 C NMR,elemental analysis and etc.Through self-assembly,the ligand can react with Ni2+ ions to form the corresponding nickel complex.And the crystal structure of the complex was characterized by X-Ray diffractometer.The result shows that the nickel-metal complex which has three core clusters of nickel is Ni3(C17H11N2O4)2(C5H5N)2(C3H7NO)2,monoclinic crystal system,space group P2(1)/n,Cell parameters: a= 13.9465(18)?,b=10.0082(9)?,c= 17.2947(16)?,?=90 deg,?=96.713(2)deg,? =90 deg,Z=2,Calculated density= 1.517 g/cm3,V= 2397.4(4)A3,R1= 0.0579,wR2=0.1233,GOF=1.041.(2)The salicyhydrazide derivatives N-(3-benzoyl acryloyl)-4-methyl salicyhydrazide is designed and made by the reaction of 4-methyl salicyhydrazide and 3-benzoyl acryloyl chloride.The structure of the compound was characterized by IR,1HNMR,13 CNMR,element analysis and etc.The ligand and NiAc2·4H2O reacted to get the corresponding nickel-metal complex by self-assembly.And the crystal structure was characterized by X-Ray diffractometer.The result shows that the nickel metal complexes which have three core clusters of nickel is [Ni3(C18H13N2O4)2(C5H5N)2(CH4O)2]·2(C3H7NO),monoclinic crystal system,space group P2(1)/n.Cell parameters: a= 13.722(2)?,b=12.7817(19)?,c= 15.087(2)?,?=90 deg,?=95.878(2)deg,? =90 deg,Z=2,Calculated density= 1.498 g/cm3,V= 2632.2(7)A3,R1= 0.0481,wR2=0.1255,GOF=1.078.(3)Salicyhydrazide and ?-furancarboxylato corresponding acid chloride were used to synthesize N-(?-furoyl)Salicyhydrazide.The structure of the compound was characterized by IR,1H NMR,13 C NMR,element analysis and etc.The ligand and NiAc2·4H2O reacted to get the corresponding nickel-metal complex by self-assembly.And the crystal structure was characterized by X-Ray diffractometer.The result shows that the nickel metal complex which has three core clusters of nickel is Ni3(C12H7N2O4)2(C5H5N)2(C3H7NO)2,monoclinic crystal system,space group P2(1)/n.Cell parameters: a= 9.3368(17)?,b=9.4185(17)?,c= 22.444(4)?,?=90 deg,?=93.741(3)deg,? =90 deg,Z=2,Calculated density= 1.630 g/cm3,V= 1969.5(6)A3,R1= 0.0606,wR2=0.1140,GOF=1.288?(4)Ni3(C17H11N2O4)2(C5H5N)2(C3H7NO),[Ni3(C18H13N2O4)2(C5H5N)2(CH4O)2]·2(C3H7NO)and Ni3(C12H7N2O4)2(C5H5N)2(C3H7NO)2 are three nickel-metal compound.They have been studied for their catalytic activity by Nessler's reag ent colorimetric method.The result shows that the three nickel-metal complexes have differences in catalyzing urea hydrolysis.Under the same conditions,Ni3(C12H7N2O4)2(C5H5N)2(C3H7NO)2 which catalyzed hydrolysis of urea is stronge st,while Ni3(C17H11N2O4)2(C5H5N)2(C3H7NO)is weakest.