Boron donor ligands

Group III. Boron donor ligands. The preparation of a range of metal complexes of B6H10 has been reported (equation 42a) following preliminary publications.177-179 

K[PtCl3(C2H4)] + 2B6H10 - frans-[PtCl2(B6H10)2] + C2H4 + KC1 (42a) 

The complex possesses a novel three-centre two-electron bond, characterized by i.r., H n.m.r., and 11B n.m.r. measurements. The X-ray structure has already been reported.179 

Group III Donors. Boron donor ligands. The unusual tris(pyrazolyl)borato-complex [RuL3(CO)2X] [X = Cl, Br, or I L = (16a)] has been prepared  

The inertness of these white-yellow complexes was ascribed to strengthening of the Ru—X bond due to reduced n-acceptor power of L compared with the cyclopentadienyl group.  

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Figure 2.37 Complexes with phosphorus or boron donor ligands bridging three or four gold atoms...

Bridging boron-donor ligands, in W-CO and W-CNR with boron, 5, 653 Bridging hydrides... 

The series of neutral B-containing carbocycles as complex ligands within the theme of metal-boron donor-acceptor relationships concludes with the 4,5-dihydro-borepines. l-Phenyl-4,5-dihydroborepine is able to substitute pyridine, acetonitrile or CO... 

An additional / -donor ligand results in the most stable boron cations because of the filled octet of boron and the complete coordination sphere.583 Boron in cation 240 has a distorted tetrahedral geometry and a N(l)—B—C angle of 99.5°.583 In cation 241 the boron atom is complexed to [Cp Fe(CO)2].595 The Cp group is bonded to boron in an r 5 fashion and the Cp-B-Fe vector is essentially linear (bond angle = 177.86°). Both spectroscopic data and DFT calculations (B3LYP with LANL2DZ and 6-31 +G ... 

Iron carbonyl complexes with As, Sb, Bi donor ligands, 6, 57 with boron, 6, 7 cyanides and isocyanides, 6, 15 Fe3(CO)i2, 6, 260... 

Lewis acids like boron trifluoride form Lewis acid Lewis base complexes such as H3N BF3 with ammonia. Ammonia also forms metal complexes, the aminocomplexes (see Ammonia N-donor Ligands). Deprotonation leads to amido, imido, and nitridocomplexes (see Scheme 14). 

Anunonia N-donor Ligands Bond Lengths in Inorganic Sohds Liquids Boron-Nitrogen Compounds Carbon Inorganic Chemistry Coordination Numbers Geometries Electrochemistry Apphcations in Inorganic Chemistry ... 

Ethane- and propane-1,2-dithiolato Cp titanium derivatives have been reported. They are reduced by boron and tin hydrides.1013,1014 Mono-Cp titanium(iv) sulfido complexes have been made by treatment of CpTiCl3 with dithiols in the presence of donor ligands such as imidazole or PMe3 under different reaction conditions (Scheme 418).1015 The structures of the compounds have been reported. Electrochemical studies suggest that these compounds are formed through a radical mechanism.1016... 

It may be that hardness correlates with fractional charge on the central atom rather than its oxidation number. This rationalization receives support from observations of ligand effects. Despite a formal core possessed by both BF3 and BH3, the former compound is a hard Lewis acid, and the latter is a soft one. This occurs because hydride ions effectively reduce the charge of the boron atom in borane. This phenomenon is particularly evident with soft donor ligands from which the negative charge is easily transferred. 

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