The crystal structure of lead ethyixanthate

Abstract

Lead ethylxanthate, Pb(SSCOCH2CH3)2, is monoclinic with a= 13.267+0.016, b=4"301 +0"015, c= 22.722+ 0.016 A; fl= 109°16'+5'; the space group is P2~/c and Z=4. Through the dithiocarbonic ends the two xanthate groups are bonded with the lead atom, with a bond angle of 98.2°+ 0.9 °. The molecule is not planar, although each xanthate group, ignoring the hydrogen atoms, is almost planar. It does not possess a twofold rotation axis passing through the lead atom and it forms an asymmetric unit in the structure. A geometrical interpretation is given of the asymmetrical molecular structure in terms of the rotations of the molecular segments around Pb-S, C-S and O-S single bonds in the crystalline state. The molecules are bound together through van der Waals forces between double-bonded sulphur atoms and between methyl ends of the alkyl groups.

Polymeric bis(O-methyldithiocarbonato)lead(II)

“…Similar pyramidal Pb-atom environments and intermolecular association as found in Pb(S2COCH2CH3) 2 (Hagihara & Yamashita, 1966) and Pb(S2CO-n-C4H9) 2 (Hagihara, Watanabe & Yamashita, 1968)have been reported for the related dithiocarbamate compounds, Pb(S2CNR2) 2 [R=CH 3 (Iwasaki, 1980); R = CH2CH 3 (Iwasaki & Hagihara, 1972); R = i-C3H 7 (Ito & Iwasaki, 1980)]. A different structural type has been reported for the dithiophosphate derivative, Pb[S2P(i-OC3HT)2]2 (Lawton & Kokotailo, 1972), in which, like that found for Pb(S2COCH3)2, the Pb atom is six coordinate.…”

“…These studies have now been extended to the Pb xanthates. The Pb ~ bis(xanthates)R = CH2CH 3 (Hagihara & Yamashita, 1966) and R = n-C4H 9 (Hagihara, Watanabe & Yamashita, 1968) show pyramidal environments about the Pb atoms and weak intermolecular Pb...S interactions (> 3.3 A) in their respective crystal lattices (perhaps indicating a propensity for polymerization). The crystal structure of the title compound, Pb(S2COCH3)2, has been determined in order to investigate the nature of the Pb-atom geometry when coordinated by the -S2COCH 3 anion given the above observations.…”

“…Molecular structure and numbering scheme for polymeric Pb(S2COCH3) 2 (Johnson, 1971). Yamashita, 1966) and Pb(S2CO-n-C4H9) 2 (Hagihara, Watanabe & Yamashita, 1968). In the latter compounds the molecules are essentially discrete with the Pb atoms existing in pyramidal geometries.…”

Crystal and molecular structure of bis-(N,N-diethyldithiocarbamato)tin(II)

“…With Pb(II), several structures containing PbSzX (X=C,P) rings have been determined (lead ethylxanthate, Hagihara & Yamashita, 1966;lead isopropylxanthate, Hagihara, Yoshida & Watanabe, 1969;lead n-butylxanthate, Hagihara, Watanabe & Yamashita, 1968;lead diethyldithiocarbamate, Iwasaki & Hagihara, 1972;lead diethyldithiophosphate, Ito, 1972;and lead diisopropyldithiophosphate, Lawton & Kokotailo, 1969). Except for the latter, all have the following common features: Pb is coordinated to four S atoms, the ligands are bidentate, Pb-S bond lengths for a given ligand are unequal, and all may be considered to be derived from the coordination in yellow PbO .…”

“…Interest in these compounds has centered on their practical applications (Hagihara & Yamashita, 1966;Klug, 1966) and in the nature of the metal-ligand bonding. In general, the coordination geometries of dithiocarbamate complexes have been found to be irregular.…”