Bidentate nitrogen ligand

With Hg2 bidentate nitrogen ligands form complexes that have chain structures. For example, 1,4-diazine III forms a complex [Hg2(C4H4N2XN03)2] (IV) that has Hg—Hg units joined in infinite chains, with the [N03] groups between the chains . ... 

Figure 1.27 Structure of the anionic, bidentate nitrogen ligands [hpp] and [tbo] ...

Complexes of zinc dialkyldithiocarbamates with bidentate nitrogen ligands such as 1,10-phen-anthroline have been structurally characterized.563 The related complexes (4,4 -bipyridyl)... 

Early NOE studies on cationic Pd(ii) allyl complexes used reporter ligands [97, 98], i. e. simple bidentate nitrogen ligands, such as bipy or phenanthroline, whose... 

Whereas the simple bidentate nitrogen ligands proved to be rather limited, the frequent occurrence of a set of four P-phenyl or alkyl substituents, e. g., in coordinated Binap, MeO-Biphep, Josiphos or Duphos (shown, from left to right in Scheme 1.4), offered many more reporters . In this way, one can develop a more detailed NOE picture of how the complexed substrate interacts with the chiral pocket offered by these auxiliaries. From these NOE studies [97, 98] it can be shown that the atropisomeric bidentate ligands Binap and MeO-Biphep tend to have fairly classical axial and equatorial P-phenyl substituents. 

The stoichiometry and IR spectrum of [CufSb eHj ] 3(N03)] are therefore consistent with a four-coordinate derivative containing unidentate nitrate. This complex has been shown to be useful for the preparation of complexes of the type [Cu(N,N)2] N03 (7V,jV-bidentate nitrogen ligand such as 1,10-phenan-throline).19... 

Styrene Vinylarenes such as styrene and its derivatives, show different behaviors from those of aliphatic 1-alkenes described above. Completely alternating head-tail copolymer of styrene and CO can be obtained by using a Pd catalyst with an achiral bidentate nitrogen ligand, 1,10-phenanthroline or 2,2 -bipyridyl, but this copolymer is >90% syndiotactic (Eq. 7.16)... 

The high electrophilicity of the silicenium ion can be modified by intramolecular electron donation from remote substituents. Corriu and co-workers668 were the first to synthesize species 269 with the bidentate nitrogen ligand. Cations with other structural units and donor atoms (O, S, P) were subsequently generated.669-674 Due to the interaction called internal solvation,675 the silicon atom becomes pentacoordinated and largely loses its ionic character, that is, such ions differ in principle from the trivalent silicenium ions. 

Bidentate nitrogen ligand (2, 2,-dipyridylamine) tethered covalently to the tip of PEG has been synthesized for the stabilization of palladium nanoparticles during alcohol oxidation in scC02/PEG biphasic media [71]. 

Table 13 The Numbers of Known Compounds MnX2- L for the Bidentate Nitrogen Ligands...

The halo ligands of these complexes can be replaced by other anionic ligands.918 One of the mutually trans tertiary arsine ligands can be replaced by other monodentate ligands such as pyridine (equation 215). Two ligands can be replaced by bidentate nitrogen ligands (equation 216) 1014 these latter products are discussed below in Section 48.6.3.6. 

A model for such a reaction sequence is (21-XLIV).184 In the case of Pd11 complexes of rigid bidentate nitrogen ligands, products of multiple successive insertions of alkenes and CO have proved isolable.185 The insertion of an alkene into the Pd—acyl bond of a neutral acyl chloro complex leads to displacement of the halide ligand and formation of a chelate-stabilized product (21-XLV).186... 

The catalysts for transfer hydrogenations are usually late transition metal complexes with tertiary phosphine ligands or bidentate nitrogen ligands, and the donors are usually organic compounds whose oxidation potential is sufficiently low to tolerate hydrogen transfer under mild conditions. Suitable donors are secondary alcohols such isopropanol. This alcohol is the most convenient since it is stable, non-toxic, environmentally friendly, easy to handle (bp 82°C), inexpensive and dissolves many organic compounds. 

Complexes with Neutral Bidentate Nitrogen Ligands... 

Consistent with the finding that less flexible ligands decrease the reaction rate for carbon monoxide insertion, the rigid bidentate nitrogen ligand bis(arylimino)acenaphthene allowed the isolation and characterization of the products of successive insertion of CO and olefin (norbornadiene, NBD" ... 

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