SYNTHESES AND STRUCTURES OF SOME RU-2(5+) COMPLEXES CONTAINING WEAKLYCOORDINATING ANIONS AS AXIAL LIGANDS

The dehalogenation reactions of Ru-2(5+) complexes containing axial ch loride ions with silver salts of weakly coordinating anions are descri bed, illustrating the conditions under which the title compounds can b e prepared. The reaction between Ru-2(O2CEt)(4)Cl and AgX yields the c ompounds (Ru-2(O2CEt)(4)X)(infinity) (X =CF3SO3- (1), ClO4-, (2)); tha t between Ru-2(O2CR)(4)Cl and AgBF4 yields [Ru-2(O2CR)(4)][BF4] (R=Me (3), Et (4)); and when Ru-2(chp)(3)(O2CMe)Cl (Hchp = 2-chloro-6-hydrox ypyridine) is reacted with AgCF3SO3, Ru-2(chp)(3)(O2CMe)CF3SO3 (5) res ults. When Ru-2(chp)(3)(O2CMe)Cl is reacted with [Ag(NCMe)(4)][BF4] in stead, [Ru-2(chp)(3)(O2CMe)(NCMe)][BF4] (6) results, and when Ru-2(chp )(4)Cl is reacted with wet AgX, [Ru-2(chp)(4)(OH2)][X] (X=BF4- (7), CF 3SO3- (8)) are the products obtained. When 3 is subsequently reacted w ith 1 equiv. of pyridine, pyRu(2)(O2CMe)(4)BF4 (9) is isolated, and wh en 4 is reacted with either THF or water, [Ru-2(O2CEt)(4)(L)(2)][BF4] (L=THF (10), H2O (11)) are the products. The structures of compounds 1 , 2, 5 and 9 as determined by single crystal X-ray diffraction are des cribed. (C) 1998 Elsevier Science S.A. All rights reserved.