Synthesis of the ligand N,N '-bis(2-tert-butylthiobenzenylidene)-diethylenetriamine; its reactivity with nickel(II) salts

The synthesis of the Schiff base ligand N,N'-bis(2-tert-butylthiobenzenylid ene)-diethylenetriamaine ((t)Bu(2)L1) and its reactivity with nickel(II) sa lts is described. Reaction of (t)Bu(2)L1 with nickel chloride results in tw o different complexes, depending on the temperature of the reaction mixture . The green paramagnetic five-coordinate complex [Ni((t)Bu(2)L1)Cl-2] forms on reaction at room temperature, whereas at reflux temperature the red dia magnetic [Ni(L1*)]Cl . H2O is formed. In the ligand L1* one of the imine gr oups is hydrolysed, and the protecting tert-butyl group of the remaining th iobenzylidene is lost, resulting in a new tetradentate N3S thiolato ligand. [Ni(L1*)]Cl . H2O crystallises in the monoclinic space group P2(1)/c, with Ni-N distances of 1.860(7), 1.941(8) and 1.914(7) Angstrom and a Ni-S dist ance of 2.131(3) Angstrom. (C) 1999 Elsevier Science S.A. All rights reserv ed.