SYNTHESIS AND CHARACTERIZATION OF PHENOXARSIN-10-YL 2-R(2)N-CYCLOPENT-1-ENE-1-CARBODITHIOATE (R=H, C2H5 CYCLO-C6H11CH2) AND THE CRYSTAL ANDMOLECULAR-STRUCTURE OF THE 2-AMINO (R=H) DERIVATIVE

Phenoxarsin-10-yl derivatives of cyclopent-1-ene-1-carbodithioic acid, and its N-alkyl derivatives O(C6H4)(2)AsS2C-C5H6 NHR-2 (R=H, CH2CH3, CH2C6H11), have been prepared by reacting O(C6H4)(2)AsCl with the corr esponding ACDA 1,1-dithioic acid. The compounds were obtained by stirr ing stoichiometric amounts of the reagents in ethanol, over 24 h, at r oom temperature. The scale of the preparations were in the order of 2 mmol and the yields of the compounds ca 75%. The reactions were carrie d out in absolute ethanol. The compounds were characterized by IR, mas s and NMR (H-1, C-13) spectroscopy. The molecular structure of O(C6H4) (2)AsS2C-C5H6-NH2-2 was determined using X-ray diffractometry, achievi ng an R-value of 6.3%; this compound is monomeric and contains an asym metric monometallic biconnective 1,1-dithiolato ligand [As-S(1) 2.272( 2) Angstrom, As...S(2) 3.125(2) Angstrom]. An intramolecular hydrogen bond is established between one hydrogen atom of the NH2 group and the sulfur [S(2)] atom involved in the secondary interaction to arsenic. The dihedral angle (150.3(3)degrees) of the phenoxarsine moiety is pra ctically unaffected by substitution of chlorine on arsenic by the carb odithioato ligand.