Monomeric and dimeric ruthenium-TCNQ complexes containing phosphine ligands (TCNQ=7,7,8,8-tetracyanoquinodimethane)

Treatment of [Ru(CO)(2)(PPh(3))(2)(THF)(2)] (BF4)(2) with LiTCNQ (TCNQ = 7,7,8,8-tetracyanoquinodimethane)in dichloromethane at reflux resulted in the formation of [Ru(CO)(2)(PPh(3))(2)(TCNQ)]BF4 (1). The synthesis of the carbonylhydride compound [RuH(CO) (PPh(3))(2)(TCNQ)](2) (2) was carried out by reaction of RuHCl(CO)(PPh(3))(3) and TCNQ or from [RuH(CO) (PPh(3))(2)(CH3CN)(2)]PF6 and LiTCNQ. The preparation of compounds with diphosphines [Ru(dppe)(2)(TCNQ)](2)TCNQ(ClO4) (3) and [Ru(dppm)(3) TCNQ]ClO4 (4) is also described. In all cases substitution reactions of labile ligands occurred with formation of compounds with sigma-coordinated TCNQ. From IR, UV-vis, H-1 and P-31 NMR spectroscopy and FAB mass spectrometric determinations, monomeric and dimeric compounds are proposed.