On the reactions of bisdiolatotungsten(VI) phenoxides. Syntheses, characterizations, and molecular structures of trans-[WCl2(diol)(OAr)(2)]

Coordinated phenoxide groups in [W(eg)(2)(mephe)(2)] (2a) and [W(eg)(2)(prp he)(2)] (2c) (eg = ethanediolate dianion; mephe = OC6H3Me2-2,6; prphe = OC6 H3Pr2-2,6) undergo reaction, with Br-2, leading to substitution at the para position of the phenyl rings and formation of the complexes [W(eg)(2)(OC6H 2R2-2,6-Br-4)(2)] (2b, R = Me; 2d, R = Pr-i). The reaction of complexes 2a- 2d and [W(eg)(2)(buphe)(2)] (2e) (buphe = OC(6)H(3)tBu(2)-2,4) with HCl lea ds to the displacement of one bidentate diolato ligand from the complex uni t and formation of the corresponding trans dichloro diolato bis(phenoxide) tungsten(VI) complex [WCl2(eg)(OAr)(2)] (3). The X-ray crystal structure de terminations of these compounds confirmed that all complexes 3 have a simil ar gross structure in which the chloro ligands are arranged at trans positi ons.