From tertiary arsines

B. From Tertiary Arsine Dihalide and Tertiary Arsine... 

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) ... 

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... 

The preparation and properties of 2-substituted isoarsindolines (28) have been examined in some detail. They are prepared from o-xylylene dibromide (32) by the reactions shown in Scheme 8 (50JCS1917). Isoarsindolines have many of the properties of stable tertiary arsines and form arsine oxides, methopicrates and methiodides. With concentrated nitric acid the intermediate arsine oxide is polar enough to react further to give the water soluble hydroxynitrate (33). With boiling hydriodic acid, 2-iodoisoarsindoline (34) is formed. This... 

Arsonium ylides have also been prepared from the decomposition of diazonium compounds in the presence of a tertiary arsine. Thus tet-raphenylcyclopentadiene triphenylarsorane (13) was obtained by heating diazotetraphenylcyclopentadiene at its melting point in the presence of triphenylarsine (66). 

Mohr, F., Priver, S.H., Bhargava, S.K. and Bennett, M.A. (2006) Ortho-metallated transition metal complexes derived from tertiary phosphine and arsine ligands. Coord. Chem. Rev., 250,... 

Apart from the triethylarsine972 and the tribenzylarsine974 complexes the remaining tertiary arsine complex is formed by the ditertiary arsine l,2-(Ph2As)2C2H4 clearly this cannot adopt structure (80). However, the ditertiary stibine complexes976 may well adopt structure (80), since their stoichiometry implies that only half the antimony atoms are coordinated to rhodium. 

The tertiary arsine complexes were first prepared by Dwyer and Nyholm,5 but, before the advent of NMR spectrometry, were erroneously considered to be rhodium(II) complexes.989 Further investigations have shown that in preparations starting from rhodium trihalides using a higher tertiary arsine rhodium ratio and lower reaction temperatures favor the formation of the p isomer (equations 205 and 206).986... 

The association of the amine hydrochloride with the aminoarsine complicates the purification of the aminoarsine. When aminolysis of the arsenic trihalide is followed by alkylation of the mono- or bisaminohaloarsine with a Grignard reagent to synthesize the aminoalkyl(or aryl)arsine, the stoichiometry of the reaction must be carefully controlled to avoid cleavage of the As N bond and formation of the tertiary arsine (see Section 2.1). A recent study has shown that the highest yields are obtained from the transamination... 

With increasing temperature the As-B adducts convert to the N-B adduct, except for the i-Pr compound, which is stable at room temperature, and decomposition leads to the formation 0fMe2AsAsMc2, Mc2AsH, [R2NBH2]2, andR2NH-BH3. The results from the aluminum alkyl reactions have been used to develop new syntheses to tertiary arsines (see Section 2). 

Tertiary arsines, phosphines, and stibines can also be displaced from their CuX(ZPh3)3 or Cu2X2(Z Ph3)3 (Z = As, P Z = As, P, Sb X = halogen) complexes by pyridine and related amines to give CuX(ZPh3)(amine) complexes. The structures of these are uncertain since their dissociation or decomposition in solution makes molecular weight data unreliable (176, 178). 

Platinum bis-S-chlorovinylbis-jSjS jS"- trichlorotrivinylarsine, [(CHCl=CH)3As]jPt(CH=CHCl)si.—This product results from the interaction of a dilute alcoholic solution of chloroplatinic acid and an alcoholic solution of the tertiary arsine. It crystallises from alcohol in very pale yellow needles, and from benzene in pale yellow plates, M.pt. 198° C. with decomposition. 

Cathodic cleavage of benzyl groups from resolved arsonium salts have been used to produce optically active tertiary arsines (Table 4). Some examples of interconversions... 

Equilibrium concentrations of semi-stabilized benzylidene ylides derived from optically pure arsonium salts and alkali metal ethoxides react with aromatic aldehydes to produce high yields of enantiomerically enriched tra s-2,3-diaryloxiranes and optically pure tertiary arsines with retention of configuration at arsenic (equation S)" -" . 

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