R. R. Shagidullin

UV spectra and electronic properties of para-substituted phenyldialkylarsines and their oxides

1. n nThe UV spectra of a number of para-substituted phenyldialkylarsines and their oxides were studied. n n n n n2. n nThe diethylarsinyl and diethylarsine groups behave as meta-orienters, in accord with the concept of participation of the d-orbitals of the As atom in conjugation.

Conformations of triisopropyl arsenate

Conclusions1.Triisopropyl arsenate exists in solutions and in the liquid state as an equilibrium mixture of two conformers with symmetries close to C3 and Cs.2.Both conformers of triisopropyl arsenate have been obtained in the form of crystals and characterized by spectral parameters.

Rotational isomerism in the trialkyl arsenates

1. n nStudy of vibrational spectra, dipole moments, and Kerr constants show the molecules of the trialkyl arsenates (CH3O)3AsO and (C2H5O)3AsO to each exist as two rotational isomers, the equilibrium system in each case containing these isomers in essentially equal proportions, under ordinary conditions. n n n n n2. n nIn one of these isomers the three RO groups are arranged in something close to a cis configuration with respect to the As=O bond [C3v(C3) symmetry]; in the other, one RO group is in a trans position (Cs symmetry). This last isomer is more polar and less favored energetically.

Ability of As=S group to form the hydrogen bond

The As=S group is capable of forming a hydrogen bond with phenol by functioning as the proton acceptor, in which connection the proton-acceptor capacity depends on the environment of the arsenic atom. The stability of the formed hydrogen bonds is somewhat higher than for the P=S group, but it is considerably lower than for the As=O group.

IR spectral investigation of the structures of the products of the reaction of tertiary arsine oxides with alkyl halides

1. n nThe IR spectra of adducts of the [R3AsO]2HHal composition were studied. n n n n n2. n nThe broad absorption at 750–1800 cm−1, which is separated into approximately three bands, was assigned to the absorption of the OH group, which participates in a strong symmetrical hydrogen bond. The structures of the adducts were established.

Vibrational spectra of organoarsenic compounds Communication 4. Infrared spectra and structure of cyclic arsenic-containing derivatives of pentaerythritol

1. n nThe IR spectra of a number of cyclic arsenic-containing derivatives of pentaerythritol were obtained and interpreted. The analytical characteristics of the bridge and spiran structures are discussed. n n n n n2. n nOn the basis of these data, the reaction products of arsenic trichloride with pentaerythritol and with Englunds compound possess an identical spiran structure.