Arsonium Iodide

MID900 CAS 64049-00-9 HR 3 (3-(N-METHYLCARBAMOYLOXY)PHEN-YL)TRIMETHYL-ARSONIUM IODIDE... 

METHYLCARBAMOYLOXY)PHENYL)TRIMETHA L-ARSONIUM IODIDE see GD900 1-METHYL-4-CARBETHOXY-4-PHENYLPIPERIDINE HYDROCHLORIDE see DAM700 METHYLCARBINOL see EFUOOO METHYL CARBITOL see DJGOOO METHYL-4-CARBOMETHOXY BENZOATE see DUEOOO... 

Methyl Iodide. By the action of methyl iodide on diphenyl cyanoarsine, by heating in a closed tube for 6 hours at 100° C., diphenyl methyl arsonium iodide and triiodide are obtained. The latter crystallises in violet needles which melt at 69° C. and are insoluble in water and in ether. 

When the alkyl halide is replaced by methylene iodide or ethylene chlorhydrin, an iodomethyl or a hydrotByethylarsonium compomd, respectively, results. Many arsonium iodides of the above t3rpes, and also some bromides, are obtained by the reaction depicted in the above equation. 

The quaternary iodides are crystalline compounds, form platini-chlorides, and with chlorine yield iododicMorides of the type R4ASI.CI2. Some aliphatic-aromatic arsonium iodides combine with metallic salts such as mercwic halides, auric chloride, and cadmiumiodide, whilst iodoform also forms addition compounds with some derivatives. Treatment of the iodides with a boiling suspension of silver chloride replaces the iodine by chlorine, giving R4ASCI. The latter also results when hydrochloric add is added to hydroxides of the type R4AS.OH. The hydroxides are derived from the iodides by boiling the latter with a suspension of silver oxide in water or alcohol. It is not always possible to isolate a crystalline product from this reaction, and the syrups often isolated soon absorb carbon dioxide from the air. 

In the years following, various stable heterocyclic arsonium salts were synthesized and resolved, including the isoarsinolinium iodide 4 and the spirocyclic arsonium iodides 5 and 6 , in which dissociation was unlikely to occur the optically active iodides in each case were stable in chloroform. The attempted resolutions of a variety of tetra-arylarsonium salts, however, failed, which was attributed to manipulative difficulties, particularly that of crystallization . In 1961, (-1- )-amylbenzylethylphenylarsonium bromide having [a]o -l-16.5° was isolated, but the salt was reported to racemize rapidly in solution ... 

The thermal decomposition of methylbis(2,2 -biphenylylene)arsenic(V) (20) at 250°C produces a colorless sublimate of methyl(2,2" -< -quaterphenylylene)arsine (21) in 94% yield with methyl iodide after 2 h in the refrigerator, (21) gave the arsonium iodide (22) in 86% yield (Scheme 4) <68CBI21>. 

Tris(trifluoromethyl)arsine does not form a stable arsonium iodide, although with methyl iodide the two compounds do appear to interact sufficiently to form an azeotropic mixture 173). At higher temperatures, or on ultraviolet irradiation, replacement of CF3 by CH3 occurs 30). 

The approximately tetrahedral arrangement of the bonds around the As( V) in the disulfide structure becomes the exactly tetrahedral arrangement in (C6H5)4AsI (407). The structure of this arsonium iodide consists of two interpenetrating body-centered lattices, one of (C6Hs)4As+ and the other of I. Each tetrahedral arsonium ion is surrounded by eight iodide ions at a... 

Arsonium Ylides. Arsonium ylides were first prepared by reaction between an arsonium halide and phenyUithium. Thus methyitriphenyiarsonium iodide [1499-33-8], C H gAsI, and phenyUithium give tripbenylarsonium metbylide [19365-61-8], C H yAs ... 

In the presence of molar amounts of catalyst, the chloride/iodide exchange reaction is more effective as has been shown by Brandsrom178 for the conversion of chloroaceto-2,6-xylidide into the corresponding iodide. The Finkelstein reaction is also catalyzed by phos-phonium and arsonium salts1. 

Tetrabutyl tellurium and bis[2,2 -biphenyldiyl] arsonium or phosphonium iodide formed tributyl telluronium iodide and butyl bis[2,2 -biphenyldiyl] arsenic or phosphorus1. 

HYDROXYPHENYL)DIETHYLMETHYL-, IODIDE, METHYLCARBAMATE see MID900 ARSONIUM, TETRAPHENYL-, CHLORIDE see TEA300... 

Methyl Iodide. On heating diphenyl chloroarsine with methyl iodide to 100° C. in a closed tube, a mixture of diphenyl iodoarsine (see p. 311) and dimethyl diphenyl arsonium triiodide, (CH3),(CeH,),Asl3, is obtained. 

TriaOcylarsine Oxides.—Only three compounds pf this type are known — the melliyl, ethyl, and n-propyl derivatives. The first two are formed by direct oxidation of the arsines by atmospheric oxygen, and the methyl compound also results when cacodyl oxide, (Me2As)20, in methyl alcohol solution is treated with methyl iodide and sodium hydroxide. The propyl derivative is formed when tetra- -propyl-arsonium hydroxide is heated in a stream of hydrogen. These oxides exhibit no add properties but are inclined to be feeWy basic, the ethyl compound yielding a nitrate, and the propyl compound a double compound with mercuric chloride. 

Tetramethylarsonium iodide, (CH3)4AsI.— The double compound of the iodide with arsenic tri-iodide is formed when powdered arsenic and methyl iodide are heated together at 160° to 200° C. If this reaction is carried out at ordinary temperatures or on the w ater-bath, the principal products are methyldi-iodoarsine and tetramethylarsonium iodide arsenic tri-iodide and a small quantity of cacodyl iodide arc also produced. When methyl iodide is ded to sodium arsenide in an atmosphere of carbon dioxide, the mixture on distillation gives cacodyl and tetramethylarsonium iodide, Cacodyl and methyl iodide react with evolution of heat, yielding the arsonium compound and cacodyl iodide according to the equation ... 

Alloys of arsenic with zinc and cadmium are also capable of giving the arsonium compound when heated at 160° to 180° C. with methyl iodide. It may be produced from its components, trimcthylarsinc and methyl iodide, or by heating methylarsine with an excess of methyl iodide for eight hours in a carbon dioxide atmosphere at 110° C. Arsenomethane, when heated at 100° C. with methyl iodide, ves tetramethylarsonium iodide ajvd methylarsine di-iodide see cyclo-pentamethylpenta-arsine, p. 33. 

Triphenylmethylarsonium iodide, Cj]il5)3As(CH j)I.— Triphenyl-arsine is heated for a long time with an excess of methyl iodide on die water-bath, when addition takes place. The arsonium compound crystallises in yellow plates, M.pt, 176° C., readily soluble in alcohol, less soluble in hot water, insoluble in ether. When treated with chlorine... 

The reaction product with methyl iodide yields dimethyldiphenyl-arsonium tri-iodide and phenyldi-iodoarsine in the molecular ratio of 0-95 2-08. 

Heating with alkyl iodides at 100° C. gives arsonium compounds, e.g. triphenylarsine di-iodide is converted by methyl iodide into triphenyl-methylarsonium tri-iodide. When the dihalides contain aliphatic and aromatic groupings, decomposition may occur as follows on heating ... 

Diethylphenoxarsonium iodide ciystallises in pale straw-coloured needles, M.pt. 193° C., and lO-carboxymethyl-lO-ethylpheiiax-arsonium bromide is prepared similarly to the corresponding methyl compound. 

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