Arsines -AsR

The arsines, AsRs, are among the most numerous and widely studied organo-arsenic compounds. They include both acyclic (e.g. Mc3As) and heterocyclic (e.g. cyclo-C5H10ASCH3) structures. Arsines are classified as derivatives of the parent compound ASH3 by successive substitutions to form the family of compounds R3 AsH (n = 0-3). Thus we include in this section arsine itself, ASH3, together with the primary, secondary and tertiary arsines. 

Ligands such as phosphines (PRj) and arsines (AsRs) (R = alkyl, aryl, halogen, etc.) form complexes with a variety of metals in various oxidation states. Vibrational spectroscopy has been used extensively to determine the structures of these compounds and to discuss the nature of the metal-phosphorus (M-P) bonding. Verkade reviewed spectroscopic studies of M-P bonding with emphasis on cyclic phosphine ligands. 

The thermolysis of cyclopolyarsines has been briefly reviewed. In general (AsR) compounds decompose into the arsine ASR3 and elemental arsenic AS4 or the diarsine... 

Early NMR data were obtained on trimethyl and di-methylphenyl derivatives of the group 15 elements, MeaE and MeaPhE (E = N, P, As, Sb, Bi). The methyl group chemical shift changes in each series were attributed to the electronegativity of the central atom. Subsequently, similar studies were reported by C NMR. Detailed and C NMR data have been reported for two series of tertiary arsines, RaAs and Me AsR. ... 

Co—L w 200 pm), PRj (225), AsRs (233). Few low-oxidation-state complexes have been reported and no crystal structures. The alkyl-substituted arsines of Co" are usually easily air-oxidized to Co " complexes, but this is difficult with phenyl- and aryl-arsines. Further oxidation to Co does not appear to be possible. 

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