P ligand in

Complexes Containing R2(0)P Ligands. In contrast to the relatively minor trans effect and trans influence of the wide range of neutral P-donor ligands discussed above, negative ligands based on trans influence as established in the X-ray structure of (3-benzyladenine)Co-... 

Chiral monophosphorus ligands, in hydrogenation, 10, 16 Chiral nematic phase, calamitic mesogens, 12, 200 Chiral N,P ligands, in hydrogenation, 10, 17 Chiral phosphines... 

Phosphine ligands, including P-heterocyclic entities, are often used in transition metal complexes. The phosphole derivatives are the most widely used heterocyclic P-ligands. In this part the less known transition metal complexes with 6-ring phosphines are summarized. 

Amatore, C., Godin, B., Jutand, A. and Lemaitre, F. (2007) Rate and mechanism of the reaction of alkenes with aryl palladium complexes ligated by a bidentate P,P ligand in Heck reactions. Chem. Eur. J., 13, 2002-11. 

C.A. Tolman, Steric effects of P ligands in organometallics, Chem. Revs., 77, 313, 1977. 

The metal chosen was Mo(0), the ligand sphere was tested for a very large variety of combinations of CO with C, N, O, S, and P ligands in the Mo(CO)5L, Mo(CO)4L2, and Mo(CO)3F3 stoichiometries. The ligands were decorated with functions that provide for enhanced solubility in water at physiological pH but had also tunable lipophilicity to gain liver specificity and avoid rapid excretion. 

The next efforts were directed to obtain precursors of bidentate P-ligands. In connection with the synthesis of the precursor of LuPhos and its Pt complex [59], the addition of diphenylphosphine oxide to l-phenyl-2-phospholene 1-oxide (40) was studied under MW conditions. The MW-assisted addition of other >P(0)H species was also investigated. It was found that in most of the cases, the reaction was not selective xmder MW irradiation (Scheme 14). The traditional activation of the >P(0)H species by MesAl followed by the addition of the anion so formed led to "clean" reactions [60]. 

Stereochemical aspects of the Wittig reaction have been investigated by NMR spectroscopy of the oxaphosphetane intermediates. User-friendly silanes, such as tetramethyldisiloxane and poly(methylhydrosilane) were applied in the deojygenation of different phosphine oxides. Optically active 1-all l- and l-atyl-3-phospholene oxides were also reduced by silanes, and the resulting phospholenes were utilized as P-ligands in Pt complexes.A novel deojygenation of triarylphosphine oxides was elaborated using oxalyl chloride and a Hantzsch ester (Scheme 59). ... 

Mercury(I) forms few complexes, one example is the linear [H2O-Hg Hg- H20] found in the mercury(I) nitrate dihydrate (above, p. 437), In contrast, mercury(II) forms a wide variety of complexes, with some peculiarities (a) octahedral complexes are rare, (b) complexes with nitrogen as the donor atom are common, (c) complexes are more readily formed with iodine than with other halogen ligands. 

Eldridge M D, C W Murray, T R Auton, G V Paoliniand R P Mee 1997. Empirical Scoring Functions 1 The Development of a Fast Empirical Scoring Fimction to Estimate the Binding Affinity of Ligand in Receptor Complexes. Journal of Computer-Aided Molecular Design 11 425-445. 

Fig. 7. A tethered cyclodextrin and the structure of P-cyclodextrin, the most common cyclodextrin used as a bonded ligand in Hquid chromatography.

The most complex P ligand so far characterized is the astonishing hexadentate Pio unit in [ Cr( j5-C5H5)(CO)2 5Pio] (see ref. 62 for details). 

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