Phenylarsenic acid

Three- and five-membered rings (AS2S and AS2S3) have also been structurally characterised for the arsenic-sulfur system. The diarsathiiran cyclo-(RAs)2S [R = C(SiMe3)3] is prepared by the addition of sulfur to the diarsene RAs=AsR. The non-planar five-membered ring cyclo-(PhAs)2S3 is obtained, in addition to cyclo-(PhAsS)4, from treatment of phenylarsenic acid with aqueous ammonia and hydrogen sulfide. ... 

Oxygen functionalities bonded to a metalloid are replaced by fluorine when reacted with sulfur tetrafluoride. Triphenylphosphane oxide, phenylarsenic acid,219 and triphcnylantimony oxide and its bis(trifluoroacetoxy) derivative222 can be converted by sulfur tetrafluoride into the corresponding organophosphorus, organoarsenic and organoantimony fluorides 16,20 and 21. 

Some organoarsenic compounds that are cytotoxic (toxic to tissue) have been found to have antitumor activity. One of these, which is active against breast cancer and leukemic cells, is 2-methylthio-4-(2 -phenylarsenic acid)-aminopyrimidine ... 

Phenylarsenic acid was reduced to phenylarsenious acid by treatment with sulfur dioxide and water... 

Figure 22 shows results obtained in the gas chromatography of a silylated mixture of aliphatic acids, phenylarsenic acid and hydrocarbons using a flame ionization detector and a glow discharge detector set at the silicon and arsenic wavelengths. 

Phenylarsenic dichloride 97 and phenylarsenic oxide 98 react rapidly with PDT 86 at ambient temperature to yield stable cyclic arsenic compound 99. When phenylarsenic acid 100 was treated with PDT 86, it was reduced to phenylarsenic oxide 98, which was then interacted with the second dithiol 86 to produce 2-phenyl-l,3,2-dithiarsinane 99 <2003JCH(1000)253>. Compound 99 was also prepared by Chowdhury et al. from the reaction of 1,3-dithiol 86 with phenylarsenic oxide 98 in dry dioxane (Scheme 30) <2002PS497>. 

Good yields of phenylarsine [822-65-17, C H As, have been obtained by the reaction of phenylarsenic tetrachloride [29181-03-17, C H AsCl, or phenyldichloroarsine [696-28-6], C3H3ASCI25 with lithium aluminum hydride or lithium borohydride (41). Electrolytic reduction has also been used to convert arsonic acids to primary arsines (42). Another method for preparing primary arsines involves the reaction of arsine with calcium and subsequent addition of an alkyl haUde. Thus methylarsine [593-52-2], CH As, is obtained in 80% yield (43) ... 

The phenylarsenous oxide solution is most conveniently prepared from phenyl-dichloroarsine, which is readily available from phenylarsonic acid. Crude phenylarsonic aoid (404 g., 2 moles) is dissolved in concentrated hydrochlorio aoid (700 cc.) and treated with a stream of sulfur dioxide. From time to time a trace of potassium iodide solution is added (0.2-0.5 g. of potassium iodide is usually sufficient to complete the reduction). When the hydrochloric acid solution becomes clear and the addition of more potassium iodide does not form a permanent cloudiness the reaction is complete. Two to three hours is usually required for this reaction. The crude phenyldichloroarsine separates as a heavy oil. The oil is removed, dried with calcium chloride, and fractionally distilled at reduced pressure in a stream of carbon dioxide or nitrogen. The nearly colorless product boiling at 140-143°/40 mm. is collected it weighs 334-400 g. (75-90%), depending on the purity of the original phenylarsonic acid. 

Phenylarsenic chloride, CgHs-AsCli, is decomposed by acetic acid, losing two chlorine atoms ... 

Phenylarsenic chloride, CgHg.AsClg, is prepared as described above. It crystallises in yellow needles, M.pt. 45° C., transformed by moist air to the oxychloride, CgHgAsOClg, and finally to phenylarsinie acid. When the dhloride is heated in a sealed tube at 160° C. it is... 

Phenylarsenic oxychloride, CgHsAsOClj, may be prepared by treating the above tetrachloride with the requisite amount of water, or in quantitative yield by the action of chlorine on phenylarsenoxide. It is a white, crystalline substance, melting at about 100 C., fumes slightly in air, dianging to the acid. It is readily soluble in water, the acid crystallising from the solution. Heated at 120 C. it is decomposed into chlorobenzene and arsenious oxychloride. In a similar manner phenylarsenic oxybronvide is produced by the action of bromine on phenylarsenoxide. 

Attempts to extend the reductive preparative procedures for phenylarsenic to phenyl-antimony have met with little success. Reduction of phenylstibonic acid or phenylanti-mony dihalides only led to polymeric materials. The phenylantimony hexamer was, however, obtained as orange or yellow crystalline solvates (PhSb)6 solv (solv = benzene, toluene, THF, 1,4-dioxane) by reaction of PhSbH2 with styrene or phenylacetylene (equation 9) or by slow reaction of PhSb(SiMe3)2 in air - (equation 10). 

---