Phosphorus ligands trigonal bipyramidal complexes

The importance of connectivity in polydentate ligands has been demonstrated by Dahlenberg.193 The classic QP ligand of Venanzi, P(o-PPh2C6H4)3, containing four phosphorus donor atoms, forms a trigonal bipyramidal complex with iron(II), [FeX(QP)]X (X = Cl, Br, I).194 When flexibility is allowed between the phosphorus donor atoms in P(CH2CH2CH2PMe3)3 a distorted octahedral... 

Phosphorus-containing macrocycles, 990, 996, 998 macrocychc effect, 1002 ring size, 1003 stereochemistry, 1003 Phosphorus heterocycles transition metal complexes, 1041 Phosphorus ligands, 989-1061 ir-acid series, 1033 bonding, 1030-1041 cone angle concept, 1012 trigonal bipyramidal complexes, 1036 Phosphorus oxychloride metal complexes, 500 Phosphorus ylides transition metal complexes, 1056 Phosphorylation biological, 978 Phosvitin, 975 Photochromism... 

The ligand (298), coordinating through phosphorus and all three sulfurs, stabilizes iron(IV) in [Fe(298)Cl], which is the first stable trigonal bipyramidal iron(IV) complex to be prepared. 

Kinetics and Mechanisms of Ligand Replacement Reactions in Trigonal Bipyramidal Nickel(II) Complexes of a Tetradentate Ligand Containing an Apical Phosphorus Donor Atom... 

NMR measurements of 1H, 13C, and 31P may be very informative about the structure of the complex. The hydride precursor of the catalyst has a trigonal bipyramidal structure in which the two phosphorus ligands present can occupy either two equatorial sites or one axial and one equatorial site (Fig. 6.6). 

A tridentate bis(amido)phosphine ligand, (MejSiNFlCFlgCF PPh, is employed to prepare several Zr(iv) complexes including the dichloride, dialkyl, and mixed alkyl complexes 190, via standard amine elimination and alkylation methodologies.165 The mixed methyl benzyl dialkyl complex shows a distorted trigonal bipyramid in which the methyl group is in the apical position trans to phosphorus and the 7]2-benzyl group is cis to phosphorus. Related... 

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