SYNTHESIS AND STRUCTURES OF RUTHENIUM(II) MONO[1,2-PHENYLENEBIS(DIMETHYLARSINE)] COMPLEXES - PRECURSORS TO TRANS METAL-TO-LIGAND CHARGE-TRANSFER CHROMOPHORIC ASSEMBLIES

The complex fac-[RuCl3(pdma)(NO)][pdma = 1,2-phenylenebis(dimethylarsi ne)] reacts with silver(I) salts, AgX, at room temperature in acetonit rile to afford disubstituted derivatives cis-[RuClX2(pdma)(NO)] (X- = trifluoroacetate 1, p-toluenesulphonate 2 or nitrate 3). Reflux of fac -[RuCl3(pdma)(NO)] in 1:4 pyridine/methanol containing an excess of Ag O2CCF3 causes conversion into cis-[Ru(OMe)(pdma)(py)(2)(NO)][PF6](2) 4 (py = pyridine). Reaction of fac-[RuCl3(pdma)(NO)] in refluxing 1.7 p yridine/acetonitrile containing 2 equivalents of AgO2CCF3 affords cis- [RuCl(pdma)(py)(2)(NO)][PF6](2) (5). 5 is also prepared by reaction of 1 in refluxing pyridine/acetonitrile. The mixed-chelate salts trans-[ RuCl(pdma)(L-L)(NO)][PF6](n) [n = 2, L-L = 2,2'-bipysidine 6, 1,10-phe nanthroline 7, 4,4'-dimethyl-2,2'-bipyridine 8 or 1,2-bis (diphenylpho sphino) ethane 9; n = 1, L-L = picolinate 10] are produced by reaction of fac-[RuCl3(pdma)(NO)] with an excess of L-L in refluxing methanol. The yields of the reactions to produce 5-10 vary according to the lig ating ability of the incoming ligand(s); Single-crystal structures of fac-[RuCl3(pdma)(NO)], 2 . Me2CO, 3 and 6 have been determined. 3 is t he first ruthenium complex containing monodentate nitrate ligand(s) to be structurally characterized. (C) 1998 Elsevier Science Ltd. All rig hts reserved.