Novel thermal reactions of two geometrical isomers of [Ru(OAc)(2cqn)(2)NO](H2cqn=2-chloro-8-quinolinol)

The thermal reactions of two isomers (cis-1 and cis-2) of [Ru(OAc)(2cqn)(2) NO] (H2cqn = 2-chloro-8-quinolinol) were studied. In deaerated DMF or DMSO at 373 K, cis-1 [Ru(OAc)(2cqn)(2)NO] isomerized to its cis-2 isomer, while cis-2 [Ru(OAc)(2cqn)(2)NO] is stable. However, at a higher temperature, 413 K, the novel thermal reaction was observed for both cis-1 and cis-2 [Ru(OA c)(2cqn)(2)NO]. Both of them gave the same products, cis-1 [RuCl(2cqn)(2oqn )NO] (H2oqn = 2,8-quinotinediol), cis-2 [RuCl(2cqn)(2)NO], and [RuCl(qn-O-q n)NO] (Hqn-O-qnH = bis(8-hydroxyquinoline-2-yl) ether); the acetato ligand was substituted for the chloro ligand derived from the 2cqn ligand, and two ligands, 2oqn and qn-O-qn, were formed from the 2cqn. The crystal structur es of cis-1 [RuCl(2cqn)(2oqn)NO] and [RuCl(qn-O-qn)NO] were determined by X -ray diffraction. (C) 2001 Elsevier Science B.V. All rights reserved.