Neutral bridging ligands

The new arsino(phosphino)methanes with bulky substituents at the two donor centers can behave both as chelating and bridging ligands toward palladium(II). Besides neutral and mono- as well as di-nuclear cationic compounds, in which these ligands are bonded in a chelating fashion, a di-nuclear complex of the A-frame type could also be generated (see Scheme 5).396... 

Alike metallocomplex anion-radicals, cation-radicals of odd-electron structure exhibit enforced reactivity. Thus, the 17-electron cyclopentadienyl dicarbonyl cobalt cation-radical [CoCp(CO)2] undergoes an unusual organometallic chemical reaction with the neutral parent complex. The reaction leads to [Co2Cp2(CO)4]. This dimeric cation-radical contains a metal-metal bond unsupported by bridging ligands. The Co—Co bond happens to be robust and persists in all further transformations of the binuclear cation-radical (Nafady et al. 2006). 

Treatment of K[Pt(0,O-MeCOCHCOMe)(C-MeCOCHCOMe)X] with mineral acids affords a material, formulated as Pt(0, -MeCOCHCOMe)Cl(MeCOCH2COMe) in which neutral, enolic acetylacetone is rc-bonded to platinum via the C=C bond. On standing, solutions of this material in chloroform yield red [Pt( -Cl)(MeCOCHCOMe)] . Similar acidification of K[Pt(MeCOCHC-OMe)3] with HX (X = Cl, Br) yields Pt(l,3,5,7-tetramethyl-2,6,9-oxabicyclo[3.3.1]nona-3,7-diene)2X2,248 whereas sulfuric, phosphoric or nitric acid leads to polymeric [Pt(MeCOCHCOMe)2]. This compound, which is isomeric with the familiar Pt(0,O-MeC0CHCOMe)2, may aggregate by means of tridentate C,0,0-MeCOCHCOMe bridging ligands.244... 

Type III bridging ligands are more susceptible to nucleophilic attack with extrusion of a neutral sulfur atom than are type la ligands. This is consistent with a generally lower electron density on the S atoms of type III ligands (bonded to two metal atoms) than of the type la ligands (bonded to one metal atom). 

Homodinuclear Neutral Mixed AuVAu111 Complexes with no Aryl Bridging Ligands... 

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