名称:
Preparation and characterization of zinc(II) and palladium(II) complexes with 16-ethyl-5,6,7,8,9,14-hexahydrodibenzo[b,i][1,4,8,11]-tetraazacyclotetradecine
摘要:
The zinc(II) and palladium(II) complexes of 16-ethyl-5,6,7,8,9,14-hexahydrodibenzo [b,i][1,4,8,11] tetraazacyclotetradecine (HL(1)) and 5,14-dihydro-7,16-diethyldibenzo[b,i] [1,4,8,11]tetraazacyclotetradecine (H(2)L(2)) have been synthesized and their spectroscopic data determined. The absorption bands of ML(1)X (M = Zn,Pd; X = Cl, NCS, ClO4) observed in the 20,400-23,900 cm(-1) region were attributable to pi-pi* and charge transfer transitions. Those bands for the three palladium(II) complexes (PdL(1)X) are similar to each other in various solvents, but the bands of ZnL(1)X are slightly different from one another. The C-13 NMR signals for NiL(1)(ClO4) and PdL(1)(ClO4) are similar to each other, but the C(15) and C(17) carbon signals for ZnL(1)(ClO4) exhibit downfield shifts upon metal coordination. Judging from the molar conductances for the complexes, ZnL(1)(ClO4) and PdL(1)X (X = Cl, NCS, ClO4) are 1:1 electrolytes in acetonitrile and nitromethane, but ZnL(1)Cl and ZnL(1) (NCS) are non-electrolytes. The treatment of PdL(1)X (X=Cl, NCS, ClO4) in methanol solution with an excess of base in air gave (7-ethyldibenzo[b,i][1,4,8,11]tetraazacyclotetradecinato)palladium(II) (PdL(3)). Copyright (C) 1996 Elsevier Science Ltd