Arsine, tris

Trimethylarsine gives a 98% yield of trimethylarsine difluoride when treated with xenon difluoride [102] in fluorotrichloromelhane. and tnsfpentafluorophen-yl)arsine gives a 94% yield of tris(pentafluornphenyl)arsme difluoride after reaction with dilute fluorine in fluorotnchloromethane at 0 C [106] Other trivalent arsenic compounds have also been fluorinated with xenon difluoride [103] In addition, arsines have been oxidatively fluorinated by iodine pentafluoride [107] or electrochemically in 26-34% yield [108]... 

Both von Hirsch 1U) and Weingarten and White 39) have reported the amination of aldehydes and ketones by tris(dimethylamino)arsine (142) to yield the corresponding gem diamine (143) or enamine (144). Von Hirsch s... 

A reagent more reactive than tris(dimethylamino)arsine employed by Weingarten and White 39) was tetrakis(dimethylamino)titanium (145). With this compound it was possible to prepare N,N-dimethyl(l-isopropyl-2-methylpropcnyl)amine (147) from diisopropyl ketone. Weingarten and White 39) have suggested a possible mechanism for this reaction (see p. 88). If benzaldehyde 39,111), formaldehyde 111), or acetaldehyde 39) is used, the corresponding gem diamine or aminal (143) is formed. 

A. Preparation.—The first reverse Wittig olefin synthesis has been reported. Triphenylphosphine oxide and dicyanoacetylene at 160 °C gave the stable ylide (1 78%) the reaction was reversed at 300 °C. No comparable reaction was observed with a variety of other activated acetylenes but tri phenyl arsine oxide gave the corresponding stable arsoranes with dicyanoacetylene (— 70 °C), methyl propiolate, hexafluorobut-2-yne, dimethyl acetylene dicarboxylate, and ethyl phenylpropiolate (130 °C). 

The arsenic compounds most commonly found in environmental and biological materials, and in working places, are arsenite and arsenate ions [As(III) and As(V)], monomethylarsonic acid (MMA), dimethylarsinic acid (DMA), arsine, di- and tri-... 

The reaction is complete when the clear supernatant solution in the reaction vessel no longer contains chlorine as detected by the addition of dilute nitric acid and silver nitrate solution to ca. 1-ml. of the clear solution withdrawn from the reaction flask. After the reaction is complete, the ice bath is removed, and stirring is continued for 2 hours at room temperature. After standing overnight, the dimethylammonium chloride is filtered and washed with n-hexane, with careful exclusion of the moisture of the atmosphere. The combined filtrates are distilled at atmospheric pressure to remove the solvent. The tris(dimethylamino)arsine distills at 36°/2 mm. (55 to 57°/10 mm.). The yield is 402 g. (78%). 

Tris(dimethylamino)arsine (d2o 1.1248 nd 1.4848)3 is a colorless liquid which is readily hydrolyzed to form arsenic (III) oxide and dimethylamine when brought into contact with water. The compound is soluble in ethers and hydrocarbons. The product is at least 99.5% pure (with respect to hydrogen-containing impurities) as evidenced by the single sharp peak at —2.533 p.p.m. (relative to tetramethylsilane) seen in the proton nuclear magnetic resonance spectrum of the neat liquid. 

The reaction of toluene solutions of indium trichloride and tris(trimethylsilyl)arsine resulted in the formation of a very fine dark-brown powder subsequently annealed up to 400°C to drive to completion the elimination of trimethyl-silyl-chloride. Nanocrystalline InAs was obtained. Similar reactions with InBr3 and Inl3 and P compounds have been discussed. Previously a similar reaction was described by Uchida et al. (1993) (reaction of indium acetylacetonate with tris(trimethylsilyl)arsine in refluxing triglyme). Subsequently the reaction with InCl3 was used by Guzelian et al. (1996) in the preparation of nano-crystal quantum dots. They compared different preparation methods and techniques useful to isolate specific size distributions. 

ARSENIC TRI BROMIDE ARSENIC TRICHLORIDE ARSENIC TRIFLUORIDE ARSENIC PENTAFLUORIDE ARSINE... 

Phosphines and arsines containing more than one olefinic group were neglected as possible multidentate ligands until Hall prepared the tris (orfAo-vinylphenyl) derivatives of phosphorus, arsenic and antimony (tvpp, tvpa and tvps) and their platinum(II) (48) and rhodium(I) (49) complexes. 

In l,3,4-oxadiazolo[3,2-a]pyridinium salts (15) an 0/As exchange can be achieved with tris(tri-methylsilyl)arsine in boiling acetonitrile to yield l,2,4-diazaarsolo[l,5-a]pyridines (16) (R = Me, Pr, Bu, Ph) (Equation (4)) <87TLl5li>. In a corresponding way the compound (17) with R = O-TMS is obtained. Methanolysis gives the hydroxy derivative (18) which exists exclusively in this tautomeric form and which can be O-acylated via the sodium salt (Scheme 3) <88TL3387>. 

Analogous to 1,2,3-benzazadiphospholes (Section 4.22.10) 1,3,2-benzazaphosphaarsole (39) and 1,3,2-benzazaphosphastibole (37) results from the condensation of 2-aminophenylphosphine (38) and tris(dimethylamino)arsine or stibine (Scheme 9) <93PS(76)45>. 

Trivinylarsenic, Tris(vinyl)arsine TX-60, Methylphosphonothioic acid S-[2-[bis(l-methylethyl)amino]ethyl] o-ethyl ester... 

VS Trivinylarsenic, Tris (vinyl) arsine No No Violent irritant... 

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