Phosphines triethylphosphine

Not surprisingly, the dipole moments of 1 1-complexes of phosphines and aluminium chloride are very large. Triethylphosphine also forms a 2 1 complex whose very low dipole moment suggests a symmetrical structure such as (139). ... 

In the presence of air, trimethyl, triethyl, and tributylphosphine combust spontaneously. In the presence of pure oxygen, even though it was at a low temperature, triethylphosphine detonated. In the same conditions, triphenyl-phosphine does not seem to be dangerous. Trimethylphosphine can be stored safely in the air in the form of a complex with silver iodide. 

Caution. Triethylphosphine and tetrakis(triethylphosphine)platinum(0) are extremely air-sensitive. The phosphine is malodorous and toxic. Therefore all... 

Tetrakis(triethylphosphine)platinum(0) is extremely air sensitive and readily soluble in saturated aliphatic hydrocarbons. The complex can be stored under dry nitrogen in a freezer (-35°) for several months. The complex readily loses one of the coordinated phosphine molecules to give Pt(PEt3)36 (dissociation constant (K ) in heptane is 3.0 X 10" ). The H NMR spectrum measured in benzene-d6 shows two multiplets at 5 1.56 (CH2) and 1.07 ppm (CH3). Tetrakis-(triethylphosphine)platinum(O) is a strong nucleophile and reacts readily with chlorobenzene and benzonitrile to give a-phenyl complexes PtX(Ph)(PEt3)2 (X = Cl, CN).7 Oxidative addition of EtOH affords [PtH(PEt3)3] +. 

Except for 1-ethynylcyclohexanol, it appears that the addition of protonic acid to triphenylphosphine platinum hydrides is unfavorable. Nevertheless, the existence of such complexes with triethylphosphine ligands is proved sufficiently since, in addition to the isolation of complexes with hydrochloric acid (10, 14), good evidence is presented for the intermediacy of triethylphosphine Pt(IV) hydrides with silanes and phosphines (15,16). 

Carbon disulphide also combines with tertiary amines 1 and phosphines, forming crystalline substances, the most important of which is a scarlet compound with triethylphosphine, CSa.P(C2H5)3, to which the constitution CS—P(CaH5)a is attributed.2 This substance is formed... 

X-ray diffraction provides a structural analysis of the adduct obtained between acetone and triethylphosphine (155) in the presence of bromine. The process of obtaining 155 is an acid-catalysed process, while the adducts obtained in the presence of chlorotrimethylsilane may be ascribed to neutral attack of the nucleophile leading to the zwitterionic complex, as shown in Scheme 46. In Scheme 46 triethylphosphine may be substituted by trimethylphosphine. When triphenylphosphine or tributylphosphine were used, no reactions were observed, owing to the reduced nucleophilic power of the bulky phosphines and to the insolubility of the obtained adducts. 

Two common phosphine oxides are triethylphosphine oxide (each R is a C2H5 group) and tribu-tylphosphine oxide (each R is a C4H9 group). The former is a colorless, deliquescent, crystalline solid (mp, 52.9°C bp, 243°C). The latter is a crystalline solid (mp, 94°C). Both compounds probably have high toxicities when ingested. 

A solution of 20.8 g. (55 mmoles) of potassium tetrachloro-platinate(II) in 100 ml. of water is prepared in a 250-ml. suction flask with a nitrogen flow through the sidearm to provide an inert atmosphere. (The procedures work equally well at halfscale.) Triethylphosphine (15 ml., 100 mmoles) is added all at once and the mixture is stirred with a magnetic stirrer at room temperature for one hour. A pink-tan precipitate of tetrakis-(triethylphosphine)platinum(II)tetrachloroplatinate(II) forms. The mixture is heated on a steam bath for one hour. The pink salt dissolves, and a layer of pale yellow dichloro-bis(triethyl-phosphine)platinum forms on the liquid. The solid is filtered, washed with water, crushed in a mortar, and dried under... 

Rapid polymerization followed when the monomer was added to tertiary amines and phosphines such as triethylamine, triethylphosphine, JV-ethylpiperidine, or pyridine. However, polymerizations initiated by tertiary amines with bulky substituents took hours rather than minutes. Primary and secondary amines were even less effective, whereas aromatic amines such as aniline and N, iV-dimethyl-p-toluidine did not cause polymerization. 

Meanwhile attention hkd been paid to the copper(I) iodide-tertiary phosphine and arsine derivatives 86). An aqueous solution of potassium iodide containing cuprous iodide, when shaken vigorously with, for example, triethylphosphine, rapidly deposited white pellets of composition... 

The derivatives with triethylphosphine and ethylene, styrene, stilbene, and methylstyrene have been prepared from bispentan-2,4-dionatonickel and alkylaluminum compounds in the presence of the phosphine and the olefin 200). The oxidation number of nickel in these compounds is controversial because the compounds can be considered to be either trico-ordinated nickel(O) derivatives (1) or square planar nickel(II) derivatives (2). 

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