Triphenylphosphine and Carbon Monoxide

OXYGEN ATOM TRANSFER FROM METAL PHOSPHINE HYDROPEROXIDES AND SUPEROXIDES 

The involvement of hydroperoxy metal complexes in oxidation reactions has been variously postulated and discussed. Metal hydroperoxides and alkylperoxides can be potentially prepared from hydrogen peroxide or alkylperoxides. Alternately, it is apparent that since a dioxygen molecule coordinated to a low-valent phosphine metal complex is an 

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A catalytic decomposition of triphenylphosphine has been reported [38] in a reaction involving rhodium carbonyls, formaldehyde, water, and carbon monoxide. The following reactions may be involved (Figure 2.39) ... 

Water and carbon monoxide can produce dihydrogen in situ (shift reaction), as has been shown in the synthesis of diethylketone (pentan-3-one) from ethene, CO and water in the presence of palladium(II) salts, triphenylphosphine and acids [37], Ether chain ends have been observed in some polymerization reactions [40] and low molecular weight products can also contain an ether moiety as an end group. Most likely ether chain ends are not formed by attack of alcohol at coordinated ethene in a Wacker type reaction, since this is usually followed by fast (3-hydride elimination. Instead we propose that a palladium-... 

A mixture of palladium chloride and triphenylphosphine effectively catalyzes carboxylation of linoleic and linolenic acids and their methyl esters with water at 110°-140°C and carbon monoxide at 4000 psig. The main products are 1,3-and 1,4-dicarboxy acids from dienes and tricarboxy acids from trienes. Other products include unsaturated monocar-boxy and dicarboxy acids, carbomethoxy esters, and substituted a,J3-unsaturated cyclic ketones. The mechanism postulated for dicarboxylation involves cyclic unsaturated acylr-PdCl-PhsP complexes. These intermediates control double bond isomerization and the position of the second carboxyl group. This mechanism is consistent with our finding of double bond isomerization in polyenes and not in monoenes. A 1,3-hydrogen shift process for double bond isomerization in polyenes is also consistent with the data. 

Trimethylene oxide also reacts rapidly with cobalt hydrocarbonyl and carbon monoxide at 0° C to produce 4-hydroxybutyrylcobalt tetracarbonyl, identified by means of its triphenylphosphine derivative, and the reaction of the tetracarbonyl with dicyclohexylethylamine to produce y-butyrolactone... 

Reactions of Vinylthiophens and Related Compounds. - 2-Aroyl-5-vinyl-thiophens react with triphenylphosphine, palladium chloride, and carbon monoxide to give 2-(5-aroyl-2-thienyl)propionic acid. Cycloaddition of sulphene, from methanesulphonyl chloride and triethylamine, to 2-(a-dimethylaminovinyl)thiophen gave (160). The synthesis of some substituted 3-(2-thienyl)acryloylamino-acids has been described. Some reactions of 3-chloro-j8-(2-thienyl)vinylphosphonic acid dichlorides have been studied, ... 

The protonated form of Fp can add to conjugated carbonyl derivatives such as acrylonitrile596 and also with conjugated dienes.597 Both S03598 and carbon monoxide can be inserted into the Fe—C bond of FpR.598 Protonolysis provides a synthetic route to substituted nitriles or alkenes. In each case the Fp unit can also be removed photochemically, thermally, or by treatment with triphenylphosphine. Hydride extraction to give an alkene or a diene is also known.599... 

This was the appearance of publications by W. Reppe and co-workers in followed by Badische Anilin und Soda Fabrik patents/ They showed that various triphenylphosphine complexes of nickel, especially [Ni(CO)2(PPh5)2](Ph = QHs), were more effective than other nickel complex catalysts for the polymerization of olefinic and acetylenic substances and that others, especially [NiBr2(PPh3)2], catalyzed the formation of acrylic acid esters from alcohols (ROH), acetylene, and carbon monoxide ... 

Kinetic measurements have shown that the reaction of acylcobalt tetracarbonyls with triphenylphosphine is first order in the cobalt compound and zero order in the triphenylphosphine down to at least 0.02 M (12). A first-order dissociation of the acylcobalt tetracarbonyl into an acylcobalt tricarbonyl and carbon monoxide has been proposed as the rate-determining step to explain the kinetics. The fast second step of the mechanism is then the reaction of the acylcobalt tricarbonyl with the triphenylphosphine, forming the acyl(triphenylphosphine)cobalt tricarbonyl. 

The favorable effects of phosphine ligands in catalysis have been known for more than half a century. One of the first reports involves the use of triphenylphosphine in the Reppe chemistry, the reactions of alkynes, alcohols and carbon monoxide to make acryhc esters [2]. An early example of a phosphine-modified catalytic process is the Shell process for alkene hydroformylation nsing a cobalt catalyst containing an alkylphoshine [3]. 

Caution. The synthesis described herein should be carried out in a well-ventilated fume hood because of the toxicity of metal carbonyl complexes and carbon monoxide. Triphenylphosphine is toxic, and gloves (not latex) should be worn and use a well-ventilated fume hood. 

Readily available o-bromoaminoalkylbenzenes (17 n = 1, 2, or 3) on heating with catalytic amounts of palladium acetate and triphenylphosphine in the presence of butylamine and carbon monoxide give the corresponding five-, six-, or seven-membered benzolactams (18) in good yield (40—65%). ... 

Aldehydes react with hydrosilanes and carbon monoxide in the presence of catalytic amounts of [Co2(CO)g]-Ph3P to give the l,2-bis(siloxy)-olefins (22). Triphenylphosphine is required as a co-catalyst to prevent the undesired hyd-rosilylation of the aldehyde, and for simple aldehydes yields are good. 

Ruthenium. Ruthenium, as a hydroformylation catalyst (14), has an activity signiftcandy lower than that of rhodium and even cobalt (22). Monomeric mthenium carbonyl triphenylphosphine species (23) yield only modest normal to branched regioselectivities under relatively forcing conditions. For example, after 22 hours at 120°C, 10 MPa (1450 psi) of carbon monoxide and hydrogen, biscarbonyltristriphenylphosphine mthenium [61647-76-5] ... 

The use of a catalyst such as cadmium oxide increases the yield of dibasic acids to about 51% of theoretical. The composition of the mixed acids is about 75% C-11 and 25% C-12 dibasic acids (73). Reaction of undecylenic acid with carbon monoxide using a triphenylphosphine—rhodium complex as catalyst gives 11-formylundecanoic acid, which, upon reaction with oxygen in the presence of Co(II) salts, gives 1,12-dodecanedioic acid in 70% yield (74). 

G-19 Dicarboxylic Acids. The C-19 dicarboxyhc acids are generally mixtures of isomers formed by the reaction of carbon monoxide on oleic acid. Since the reaction produces a mixture of isomers, no single chemical name can be used to describe them. Names that have been used include 2-nonyldecanedioic acid, 2-octylundecanedioic acid, l,8-(9)-heptadecanedicarboxyhc acid, and 9-(10)-carboxystearic acid. The name 9-(10)-carboxystearic acid can be used correctiy if the product is made with no double bond isomerization (rhodium triphenylphosphine catalyst system). 

Thiirane 1,1-dioxides extrude sulfur dioxide readily (70S393) at temperatures usually in the range 50-100 °C, although some, such as c/s-2,3-diphenylthiirane 1,1-dioxide or 2-p-nitrophenylthiirane 1,1-dioxide, lose sulfur dioxide at room temperature. The extrusion is usually stereospeciflc (Scheme 10) and a concerted, non-linear chelotropic expulsion of sulfur dioxide or a singlet diradical mechanism in which loss of sulfur dioxide occurs faster than bond rotation may be involved. The latter mechanism is likely for episulfones with substituents which can stabilize the intermediate diradical. The Ramberg-Backlund reaction (B-77MI50600) in which a-halosulfones are converted to alkenes in the presence of base, involves formation of an episulfone from which sulfur dioxide is removed either thermally or by base (Scheme 11). A similar conversion of a,a -dihalosulfones to alkenes is effected by triphenylphosphine. Thermolysis of a-thiolactone (5) results in loss of carbon monoxide rather than sulfur (Scheme 12). 

Soderberg and coworkers have developed a palladium-phosphine-catalyzed reductive iV-het-eroannuladon of 2-nitrostyrenes forming indoles in good yields For example, reaction of 6-bromo-2-nitrostyrene with carbon monoxide in the presence of a catalytic amount of palladium diacetate (6 mol% and triphenylphosphine 124 mol% in acetonitrile at 30 gives 4-bromoindole in 86% yield fEq 10 62 Several functional groups, such as esters, ethers, bromides, tnflates, and additional nitro groups, have been shown to be compatible with the reaction conditions... 

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