Diphenylphosphine pyridine

The polydentate ligands 2-(diphenylphosphino)-6-[3-(2 -pyridyl)pyrazol-l-yl)pyridine and 2-(diphenylphosphino)-6-(pyrazol-l-yl)pyridine react with [Ag(NCMe)4]C104 to give the dinuclear complexes where the ligands are P,N,N bonded as in (249).1 82 The reaction of two equivalents of AgBF4 with 6,6-bis(diphenylphosphine)-2,2 -bipyridyl (P2-bipy) gives the complex [Ag4(P2-bipy)2](BF4)4. Addition of Br or I leads to complexes [Ag4X2(P2-... 

The coupling of secondary phosphines with aryl iodides was also extended to pyridines. 3-Iodopyridine and diphenylphosphine were coupled to give 3-diphenylphosphino-pyridine in 60% yield (7.80.), The catalyst in this reaction consisted of copper(I) iodide and N,N -dimethylethylenediamine and caesium carbonate was used again as base.102... 

A similar acetylation reaction is known25 for various primary and secondary phosphine oxides. Besides 23 and its diastereoisomers, a complex product resulting from phosphorus-phosphorus dimerization of 15 was isolated, in 25% yield, during the aforementioned acetylation this appears to be analogous to the formation of tetraphenyldiphosphine monoxide [Ph2P - P(=O) Ph2] from diphenylphosphine oxide in the presence of acetic anhydride and pyridine at room temperature.26... 

Fig. 9.11. Reaction microarrays in high-throughput ee determination [28]. Reagents and conditions step 1, BocHNCH(R)CC>2H, PyAOP, iPi NEt, DMF step 2, AC2O, pyridine step 3,10% CF3CO2H and 10% Et3SiH in CH2CI2, then 3% Et3N in CH2CI2 step 4, pentafluorophenyl diphenylphosphinate, rPi NEt, 1 1 mixtme of die two fluorescent proline derivatives, DMF, —20°C.

Scheme 8.15 Model for enantioface selection during styrene-carbon monoxide copolymerization using diphenylphosphine- (76) or pyridine-dihydrooxazole (77,77, 78) chelate ligands and for inversion of regiochemistry of the insertion (79, 79 ) for sterically hindered diarylphosphine-dihydrooxazole ligands (GPC = growing polymer chain).

The complex serves as a useful intermediate for the preparation of other iridium(I) complexes, because the p-toluidine ligand can be readily displaced at room temperature by pyridine or 1,10-phenanthroline.2 An additional carbon monoxide ligand is replaced with triphenylphosphine, -arsine, and -stibine as well as with phosphites and ethylenebis[diphenylphosphine].2... 

Reaction of UX4 (X=C1, BH4) and two equivalents of [Li(Et20)] [SPS ], the lithium salt of an anionic SPS pincer ligand composed of a central hyper-valent Z4-phosphinine ring bearing two orf o-positioned diphenylphosphine sulfide side arms, formed complexes of the type [UX2(SPS )2] (Fig. 36). Crystals of the chloride derivative were obtained as the pyridine adduct, and... 

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