摘要:
The tetradendate macrocyclic ligands, [ H2L-1 = 5,12-dioxa-7,14-dimethyl-1,4,8,11-tetraazacyclotetradeca-1,8- diene] and [ H2L-2 = 6,14-dioxa-8,16-dimethyl-1,5,9,13-tetraazacyclohexadeca-1,9-diene] have been prepared by the condensation reaction of 1,2-diaminoethane and 1,3-diaminopropane, respectively, with ethyl acetoacetate in methanol at room temperature. The diorganotin( IV) complexes of general formula [ R2Sn( L-1)/ R2Sn( L-2)] ( R = Me, n-Bu and Ph) have been synthesized by template condensation reaction of 1,2-diaminoethane or 1,3-diaminopropane and ethyl acetoacetate with R2SnCl2 ( R = Me or Ph) or n-Bu2SnO in 2: 2: 1 molar ratio at ambient temperature ( 35 +/- 2 degrees C) in methanol. The solid-state characterization of resulting complexes have been carried out by elemental analysis, IR, recently developed DART-mass, solid-state C-13 NMR, Sn-119m Mossbauer spectroscopic studies. These studies suggest that in all of the studied complexes, the macrocyclic ligands act as tetradentate coordinating through four nitrogen atoms giving a skew-trapezoidal bipyramidal environment around tin center. Since, the studied diorganotin( IV) macrocyclic complexes are insoluble in common organic solvents, hence good crystals could not be grown for single crystal X-ray crystallographic studies. Thermal studies of all of the studied complexes have also been carried out in the temperature range 0-1000 degrees C using TG, DTG and DTA techniques. The end product of pyrolysis is SnO2 confirmed by XRD analysis. (C) 2008 Elsevier B.V. All rights reserved.