Molecular structure of 10-phenoxarsine chloride, C12H8OAsCl

Abstract

The crystal and molecular structure of 10-phenoxarsine chloride, CisHgOAsCl, has been determined by single-crystal X-ray diffraction methods. The unit cell is monoclinic: a = 5.7596 (6) A, b ~14,641 (2) A,c -13.788 (1) A, ß = 109.80 (1)°, ámeasd = 1.71 (1) g cm-3, and <Zcaicd (Z = 4) = 1,691 g cm-3. The space group is 7%% (C3hs; No. 14). Manual diffractometer methods (Mo radiation, X 0.71069 Á) were used to obtain 434 observed (I ^2 ( 7)) reflections at 23°. Final full-matrix least-squares refinement using anisotropic thermal parameters for As and Cl and assigned positional and thermal parameters for the hydrogen atoms gave an R index of 0.047. The As-Cl bond distance is 2.255 (5) A, and the average As-C distance is 1.93 (2) A. All of the bond angles at the arsenic are 94-98°. The two CgHiOAs "halves" are planar within 0.04 Á, and the angle of fold at the As••• • O line is 156.3°. A comparison of these structural parameters with those of phenarsazine chloride suggests a smaller amount of aromatic character in 10-phenoxarsine chloride.

The structure and reactivity of arsenic compounds: Biological activity and drug design

“…1/2H20 , has been crystallised (in contrast to arsenious acid). The structure consists of a 3D arrangement of tetrahedral AsO(OH)3 groups and H20 molecules linked by hydrogen bonding [30,49] 2.255 (As-C1) [58] R2AsO(OH), there is again tetrahedral coordination about As(V), e.g. phenylarsonic acid [51] and the herbicide, dimethylarsinic (cacodylic) acid [30,51].…”

“…Subsequently the structure of the ortho acid [57] showed that there was indeed an As=O bond in this type of structure. The As(III) fungicide, 10-phenoxarsine chloride [58], is included as it is possibly the only biologically active organo As(III) compound which has been structurally characterised.…”

“…Refs. [52,53,54,55,56,57,58] [Cr(CO)5 ] (C1) As [Mn(CO)2 Cp] [61]. Both P [25] and Sb [26] derivatives of the first compound are also known.…”

Structure of the phenylimide of tris(dimethylhydrazino)bis(phosphine)

“…An analysis of the weighting scheme showed no apparent dependence on [Fol or sin 0. The maximum NOTE (100), (010) and (001) Center, using programs previously described (Stuckey et al, 1972).…”

Structure of 10-(m-tolyl)-5,10-dihydrophenarsazine

“…The final atomic parameters are given in Table 1.t The identification of the atoms and the configuration of the molecule are shown in the OR TEP (Johnson, 1965) is smaller than that of 164.6(2) ° found in 10-(3-methoxyphenyl)-5,10-dihydrophenarsazine. In other similar compounds, the values of the folding angles are: 154.1 (4) ° in 10-methyl-5,10-dihydrophenarsazine (de Meester, Chu, Jovanovic & Biehl, 1986), 156.3 ° in 10-chlorophenoxarsine (Stuckey, Cordes, Handy, Perry & Fair, 1972), 169.2 ° in 10-chloro-5,10-dihydrophenarsazine (Camerman & Trotter, 1965), and 178.5 ° in 10,10'-thiodiphenoxarsine (Grindstaff, Cordes, Fair, Perry & Handy, 1972). The m-tolyl substituent is in an axial position relative to the central ring as found in the compounds already mentioned.…”