Arsines electrolytic reduction

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) ... 

Electrolytic reduction of As(III) or As(V) species in solution at the cathode yields arsine e.g., ASH3 is formed upon reduction of either As(III) or As(V) species in 0.5 N HjSO. Reduction of As(V) is more cathodic than As(III). 

The yield is about 83 per cent. The arsine may also be prepared by the electrolytic reduction of phenylarsinie acid in aqueous alcohol solution. ... 

Electrolytic reduction of o-nitroj)heny arsinic acid in a sodium acetate solution, using a water-cooled platinum eathohydrazo-benzene-o-o -dlarsinicacid,(HO)ijOAs.Ceir4.Nir.NHf.C,ir4.AsO(OII)2,... 

All the mono- and diarylarsines may be prepared by the reduction of the corresponding arsinic acids, whether the benzene nucleus is substituted or not. Such reduction may be effected with zinc dust and hydrochloric acid, and, in the case of phenylarsinic acid, electrolytic reduction in aqueous alcohol solution has also been used. The primary arsines show no basic properties and readily undergo oxidation in air, forming oxides, acids, and arseno- compounds. Halogens react with these arsines, replacing the hydrogen ... 

Optically active arsines containing alkyl groups have recently been prepared by electrolytic reduction of optically active quaternary arsonium salts 450). The optically active arsine combines with sulfur in benzene to give the active arsine sulfide. 

Polarographic data are available for a number of arsonium compounds (502), arsines and diarsines (502a, 502b). The following is a typical example of the electrolytic reduction processes encountered ... 

The Electrolytic Method is one of the most satisfactory adaptations of the Marsh process. Instead of generating arsine by the action of zinc on acid, it is produced by cathodic reduction.12 The amount of nascent hydrogen produced during electrolysis is connected with the... 

Dimethylarsinic acid appears to be the only arsinic acid studied in non-aqueous solvents. In agreement with the findings for methylarsonic acid, reduction only takes place in MeOH or in MeCN in the presence of an acidic supporting electrolyte (guanidin-ium perchlorate). In contrast to the results obtained in buffered aqueous solution, the half-wave potential for reduction of MejAsO(OH) in MeOH or in MeCN is lower than the half-wave potential for reduction of MeAsO(OH)2 under the same conditions. ... 

In acidic electrolytes containing antimony or arsenic, the evolution of noxious stibine or arsine is possible e.g. during the reduction of As(III) solutions ... 

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