Of triphenylarsine

Trialkyl- and triarylarsine sulfides have been prepared by several different methods. The reaction of sulfur with a tertiary arsine, with or without a solvent, gives the sulfides in almost quantitative yields. Another method involves the reaction of hydrogen sulfide with a tertiary arsine oxide, hydroxyhahde, or dihaloarsorane. X-ray diffraction studies of triphenylarsine sulfide [3937-40-4], C gH AsS, show the arsenic to be tetrahedral the arsenic—sulfur bond is a tme double bond (137). Triphenylarsine sulfide and trimethylarsine sulfide [38859-90-4], C H AsS, form a number of coordination compounds with salts of transition elements (138,139). Both trialkyl- and triarylarsine selenides have been reported. The trialkyl compounds have been prepared by refluxing trialkylarsines with selenium powder (140). The preparation of triphenylarsine selenide [65374-39-2], C gH AsSe, from dichlorotriphenylarsorane and hydrogen selenide has been reported (141), but other workers could not dupHcate this work (140). 

Palladium-catalyzed hydroarylation of sterically hindered PTAD adduct 157 with aryl halides in the presence of triphenylarsine, sodium acetate, and DMSO provides a 1 1 mixture of 170 and 171. The same reaction done with sodium fluoride and formic acid provides mixtures containing 171 as the major product. Apparently, the use of sodium fluoride as a base allows the selective formation of the opening products 171 in good yields (Equation 19). Similarly, the 2,3-phthalazine-l,4-dione adduct 172 provides the corresponding products 173 and 174 (Equation 20) <2002AGE3375>. 

B. 2-(4-Methoxyphenyl)-2-cyclohexen-1-one. A 500-mL, round-bottomed flask, equipped with a 1.5-in. Teflon-coated magnetic stirring bar and an argon inlet adaptor, is charged with 10.02 g (45.1 mmol) of 2-iodo-2-cyclohexen-1-one, 10.69 g (70.4 mmol, 1.56 eq) of 4-methoxyphenylboronic acid (Note 8), 16.72 g (72.1 mmol, 1.6 eq) of silver(l) oxide (Ag20) (Note 9), 0.85 g (2.8 mmol, 6 mol %) of triphenylarsine (Note 10), 0.53 g (1.4 mmol, 3 mol %) of palladium(ll) bis(benzonitrile)dichloride (Note 11), 200 mL of tetrahydrofuran (THF) and 25 mL of water (Note 12). The reaction mixture, flushed with argon, is stirred for 1 hr and then quenched by the addition of 125 mL of saturated aqueous ammonium chloride. After the solution is stirred for 1 hr, the... 

Hendrickson and co-workers reported that triphenylarsine reacts with DMAD to give tetramethyl l,l,l-triphenylarsole-2,3,4,5-tetracarboxylate (503). However, it was subsequently shown by the same workers that the product formed in this reaction is the adduct 505, not 503 (Scheme 79). Recently, Ciganek has shown that triphenylarsine oxide reacts with DMAD to give the same adduct (505) (Scheme 80). He has further suggested that the formation of 505 in the reaction of triphenylarsine may proceed through a zwitterionic intermediate (504), which reacts with water to give triphenylarsine oxide... 

The application of triphenylarsine ligand and LiCl as promoter allows for realization of carbonylative crosscoupling in complex synthetic tasks, as shown, for example, in Equations (6) and (7). ... 

C. Tetraphenylarsonium chloride hydrochloride. In a 2-1. round-bottomed three-necked flask fitted with a condenser, a mercury-sealed mechanical Hershberg stirrer, and a dropping funnel is placed 40 g. (0.124 mole) of triphenylarsine oxide dissolved in 1 1. of hot benzene. To this solution there is added with vigorous stirring a solution of phenylmagnesium bromide which is prepared from 34.6 g. (0.22 mole) of bromobenzene, 6.0 g. (0.25 gram atom) of magnesium, and 200 ml. of dry ether. A brown viscous solid separates. The mixture is stirred for 15 minutes and then stirred and heated under reflux on a steam bath for 30 minutes. The solvent is removed by decantation, and the viscous solid is washed with 500 ml. of benzene. The addition product is... 

Silver salts of triphenylarsine and triphenylstibine have also been prepared. When silver trifluoroacetate was added to a methanol-water solution of triphenylarsine, a change due to complexation was observed in the UV spectrum. The trifluoroacetate was assumed to be completely dissociated and a 1 1 complex with the arsine formed. The stability constant at 25 °C was determined as log / i = 5.7-5.8.203... 

A facile method for the preparation of a variety of stabilized arsonium ylides in good yield has been developed by the action of active methylene compounds with tertiary arsine oxide or tertiary arsine dihalide. Thus triphenyl-arsine dihalides react with a number of active methylene compounds in the presence of a tertiary amine to afford arsonium ylides (6) (40). The reaction of triphenylarsine oxide with active methylene compounds in the presence of either acetic anhydride or triethylamine-phos-phorus pentoxide gave rise to arsonium ylides (6) (32, 36. 65, 67). 

The reaction of triphenylarsine oxide with strongly acidic methylene compounds in acetic anhydride affords acetylated ylides (7) (32, 67), e.g.,... 

Arsonium ylides have also been prepared from the decomposition of diazonium compounds in the presence of a tertiary arsine. Thus tet-raphenylcyclopentadiene triphenylarsorane (13) was obtained by heating diazotetraphenylcyclopentadiene at its melting point in the presence of triphenylarsine (66). 

This method was extended to different diazonium salts and several arsonium ylides (14) were prepared (23, 32). The reaction is greatly facilitated by the presence of copper, copper-bronze, or copper salts. For example, attempts to prepare the bis(carbethoxy)methylene ylide by thermolysis of diethyl diazomalonate in the presence of triphenylarsine without the presence of a catalyst proved abortive, whereas this ylide was obtained in 61% yield if the reactants were heated at 150°C with copper-bronze (32). 

Only a few reports on studies of the mass spectra of arsonium ylides have appeared in the literature. Gosney and Lloyd (32) studied the mass spectra of bis(carbethoxy)methylene triphenylarsorane and nitromethy-lene triphenylarsorane and found that preliminary fragmentation resulted in loss of the carbanionic moiety. We studied the mass spectra of 11 arsonium ylides and of triphenylarsine difluoride (30). 

Methylene triphenylarsorane (97) reacted with a,/3-unsaturated ketones to give cyclopropanes with loss of triphenylarsine. 

The synthesis of N-sulfonylarsinimines 19 has been accomplished by a non-nitrene pathway involving the treatment of triphenylarsine with BAIB and the... 

An example that used this protocol the substrate of which contains a sensitive functionality is depicted in Scheme 45 [202]. 1,3-Diene monoepoxide is easily attacked by a palladium(O) complex to form the corresponding 7r-allylpalladium species. Thus such a process could be banished from the desired selective transformation as depicted in Scheme 46 by the employment of the alkynyltin reagent with an aid of triphenylarsine ligand [203]. Organotin protocol is also convenient for introduction of a small alkynyl moiety such as C2 or C3 or preparation of symmetrical diarylethynes (Scheme 47) [204]. Shirakawa et al. reported recently that iminophosphine 4 is much more effective ligand for palladium than tris(2-furyl)phosphine in this reaction (Scheme 48) [32,205]. 

A mixture of fig. (0.0 Ifi mol) of triphenylarsine and 2 g. (0.004 mol) of triiron dodecacarbonyl (synthesis 4fi) is either refluxed in 150 ml. of tetrahydrofuran or heated at 80 to 90° in dioxane in an atmosphere of nitrogen for 45 minutes. The mixture is then cooled and filtered. The residue is rejected. It contains very little product, inasmuch as the arsine complexes are more soluble than the... 

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