Triphenylphosphine complex

Similar activation takes place in the carbonylation of dimethyl ether to methyl acetate in superacidic solution. Whereas acetic acid and acetates are made nearly exclusively using Wilkinson s rhodium catalyst, a sensitive system necessitating carefully controlled conditions and use of large amounts of the expensive rhodium triphenylphosphine complex, ready superacidic carbonylation of dimethyl ether has significant advantages. 

For the triphenylphosphine complexes, where the ds-form is particularly stable, irradiation causes the cis-trans isomerization... 

A single-crystal X-ray analysis of the triphenylphosphine complex [Ni(PPh3)(CS2)]2 has revealed that the complex has the binuclear structure (1017). The complex [Ni(PMe3)2(CS2)2] displays NiPSCS coordination (1018) and is severely distorted from square planar. Of interest is the fact that the SC(S)SC(PMe3)S linkage can be formally described as a condensation product of two molecules of CS2 with one molecule of PMe3.2464... 

Phenylcopper -triphenylphosphine complexes Camus, A. el al., J. Organomet. Chem., 1980, 188, 390... 

Batch continuous processing, in which part of the catalytic solution is removed to a low pressure distillation unit, on the other hand, has recently been commercialised [2-4]. Very little information is available in the public domain concerning this low pressure distillation process, but the main extra cost will be in generating the reduced pressure required for the distillation. The estimated vapour pressures at 110°C of various long chain linear aldehyde products that are commercially desirable are shown in Figure 9.1. This temperature has been chosen because this is the high temperature limit above which the rhodium triphenylphosphine complex starts to decompose. Any commercial process will require to operate the product distillation step at a pressure no higher than those shown for the individual aldehydes. 

The course of the condensation of ethylene glycol with secondary amines (Me2NH, Et2NH, pyrrolidine or morpholine) depends on the catalyst used. Triphenylphosphine complexes of ruthenium, e.g. RuCl2(PPh3)3, give hydroxyalkylamines while hydrated ruthenium(III) chloride yields diamines (equation 24)62. 

In 1986 a new process came on stream employing a two-phase system with rhodium in a water phase and the substrate and the product in an organic phase. For propene this process is the most attractive one at present. The catalyst used is a rhodium complex with a sulphonated triarylphosphine, which is highly water-soluble (in the order of 1 kg of the ligand "dissolves" in 1 kg of water). The ligand, tppts (Figure 8.6), forms complexes with rhodium that are most likely very similar to the ordinary triphenylphosphine complexes (i.e. RhH(CO)(PPh3)3). 

Palladium(o) triphenylphosphine complexes catalyse the reduction of aryl bromides and iodides in a divided cell to give the diaryl [230]. The catalytic species... 

The triphenylphosphine complex 42 b reacts with bromine to give a platinum(IV) species 42f, assigned the cyclic structure with four platinum-carbon c-bonds. The reaction sequence here must begin with the attack of a bromine molecule on an uncoordinated olefin, as otherwise it is hard to see why two metal-carbon bonds are formed, and not one metal-carbon and one metal-bromine. 

Although lithiation remains the most frequently used metalation reaction, there have been a number of new reports of direct palladation of aryloxazolines. For example, Smoliakova and co-workers prepared the dimeric palladium complex 457 by direct reaction of Pd(OAc)2 with 2-phenyloxazoline in the presence of NaOAc/ HOAc (Scheme 8.150). ° The dimeric complex 457 was converted to the monomeric triphenylphosphine complex 458 for which the X-ray crystal structure was determined. A similar reaction sequence was observed for naphthalenes. Muller... 

The two complexes have absorption maxima at 524.0 nm, with concentration-dependent extinction coefficients. This concentration dependence is thought to result from a concentration-dependent distribution of molecular aggregates. Infrared spectra show only the bands associated with the ligand, the most prominent of which are 3300-3460, 1458, 1412, 1075, 730,682, and 480 cm 1 (KBr disk). Raman bands for the triphenylphosphine complex appear at 180, 124, and 90 cm 1. 

The final product can be isolated easily as the triphenylphosphine complex. This reaction is also general as far as the acylcobalt carbonyl is concerned, but the yields vary widely depending upon which acetylene is used (34). Presumably, the presence of substituents on the acetylene favors the cyclization step rather than the formation of linear products. The larger the substituents the more favorable the cyclization becomes. If cyclization does not take place relatively rapidly, linear compounds and polymers of acetylene, or of acetylene and CO are probably formed. Thus, these reactions demonstrate the insertion reaction of both acetylenes and ketonic carbonyl groups. 

The carbonylation of Af-benzyl-y-(o-bromophenyl)propylamine to give AT-benzyl-tetrahydro-2-benzazepin-l-one is catalyzed by palladium acetate-triphenylphosphine complex (78JOC1684). On treatment with 2M sodium hydroxide the aminoketone (236) undergoes ring expansion to the 2-benzazepin-l-one (237) in a manner analogous to that outlined in Scheme 28 (80HCA924). 

It has recently been shown (38a) that the triphenylphosphine complexes of platinum are in all probability complex hydrides of platinum(II), with general formula [(Ph3P)jPtTI2] where x - 2, 3, or 4. As these materials have always been used in the preparation of other platinum(O) complexes, it is now doubtful whether such complexes have in fact ever been obtained since it is possible that they are all hydrides. 

AN IRIDIUM(III) COMPLEX CONTAINING CYCLOMETALLATED TRIPHENYLPHOSPHINE FORMED BY ISOMERIZATION OF AN IRIDIUM(I) TRIPHENYLPHOSPHINE COMPLEX... 

---