Arsines tertiary

Arsines (tertiary) Perchloric acid Rudresh and Mayanna (1977, 1980)... 

Another good method for preparing secondary arsines involves cleavage of an alkyl or aryl group from a tertiary arsine and subsequent hydrolysis of the resulting secondary arsenide (47,48) ... 

Tertiary arsines have been widely employed as ligands in a variety of transition metal complexes (74), and they appear to be useful in synthetic organic chemistry, eg, for the olefination of aldehydes (75). They have also been used for the formation of semiconductors (qv) by vapor-phase epitaxy (76), as catalysts or cocatalysts for a number of polymeri2ation reactions (77), and for many other industrial purposes. 

Where X is Br or Q, the free acids may be obtained by acidification of the alkaline solution, but where X is I, the acids must be isolated as salts to avoid reduction of the arsonic acids by HI. Rather than using alkyl haUdes, alkyl or dialkyl sulfates or alkyl arenesulfonates can be used. Primary alkyl haUdes react rapidly and smoothly, secondary haUdes react only slowly, whereas tertiary haUdes do not give arsonic acids. AHyl haUdes undergo the Meyer reaction, but vinyl hahdes do not. Substituted alkyl haUdes can be used eg, ethylene chlorohydrin gives 2-hydroxyethylarsonic acid [65423-87-2], C2H2ASO4. Arsinic acids, R2AsO(OH), are also readily prepared by substituting an alkaU metal arsonite, RAs(OM)2, for sodium arsenite ... 

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). 

Although trialkyl- and triarylbismuthines are much weaker donors than the corresponding phosphoms, arsenic, and antimony compounds, they have nevertheless been employed to a considerable extent as ligands in transition metal complexes. The metals coordinated to the bismuth in these complexes include chromium (72—77), cobalt (78,79), iridium (80), iron (77,81,82), manganese (83,84), molybdenum (72,75—77,85—89), nickel (75,79,90,91), niobium (92), rhodium (93,94), silver (95—97), tungsten (72,75—77,87,89), uranium (98), and vanadium (99). The coordination compounds formed from tertiary bismuthines are less stable than those formed from tertiary phosphines, arsines, or stibines. 

In view of the excellent donor properties of tertiary arsines, it is of interest to inquire whether these cyc/o-polyarsanes can also act as ligands. Indeed, (MeAs)s can displace CO from metal carbonyls to form complexes in which it behaves as a uni-, bi- or triden-tate ligand. For example, direct reaction of (MeAs)5 with M(CO)6 in benzene at 170° (M = Cr, Mo, W) yielded red crystalline compounds [M(CO)3( -As5Me5)] for which the structure... 

Similar reactions on alkyl or aryl arsonites yield the arsinic acids R2AsO(OH) and Ar2AsO(OH). Arsine oxides are made by alkaline hydrolysis of R3ASX2 (or Ar3AsX2> or by oxidation of a tertiary arsine with KMn04, H2O2 or I2. 

Tertiary phosphine complexes have been studied intensively since the 1960s. The bulk of the work has been with phosphines, but corresponding arsine complexes are broadly similar. 

Considerable structural information is available on osmium complexes of tertiary phosphines, arsines and stibines (Table 1.13) [152, 157]. 

Rhodium(III) forms a wide range of complexes with tertiary phosphines and arsines [108, 109], though in some cases other oxidation states are possible. Table 2.5 summarizes the complexes produced from reaction of RhCl3 with stoichiometric quantities of the phosphine. 

A considerable number of the tertiary phosphine and arsine complexes of iridium(III) have been synthesized [4, 8] they generally contain 6-coordinate iridium and are conventionally prepared by refluxing Na2IrCl6 with the phosphine in ethanol or 2-methoxyethanol [154]... 

The limited stability of these compounds is shown by the fact that other tertiary phosphines and arsines do not yield isolable products. 

While tertiary phosphines and arsines tend to reduce gold(III) to gold(I), the reverse reactions can be used synthetically [126] ... 

Coordination chemistry of organomercury(II) involving phenanthrolines, bipyridines, tertiary phos-phines/arsines and some related ligands. T. S. Lobana, Coord. Chem. Rev., 1985,63,161 (186). 

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