86861-01-0Relevant academic research and scientific papers
A preparative and multinuclear nuclear magnetic resonance spectroscopic study of As(SPh)x(SePh)3-x (x=0-3), Sb(SPh)x(SePh)3-x (x=0-3), Bi(SPh)3, Bi(SePh)3, x(SePh)3-x>- x=0-3), Pb(SePh)3-, and Pb(SPh)3- and some related thiolatoplumbates(II)
Arsenault, J. J. Ivan,Dean, Philip A. W.
, p. 1516 - 1523 (2007/10/02)
The phenyl selenolates of tin(II), lead(II), arsenic(III), antimony(III), and bismuth(III), M(SePh)n (M=Sn(II) or Pb(II), n=2; M=As(III), Sb(III), or Bi(III), n=3), have been synthesized by acid-base reaction of the appropriate metal acetate (for M=Sn(II) or Pb(II)) or thiphenolate (for all five elements) with PhSeH, and characterized by elemental analysis and for the group V elements, (77)Se and (13)C nmr spectroscopy.M(SPh)2 and M(SePh)2 (M=Sn(II) or Pb(II)) are poorly soluble in MeOH but dissolve in the presence of an equimolar or greater amount of PhS- or PhSe-.The soluble stannate(II) complexes are triligated as shown by the slow exchange (119)Sn and, where appropriate, (77)Se nmr spectra of the seriesx(SePh)3-x>- (x=0-3) measured for the supernatant liquor of mixtures in whichtotal/PhE-total>1.The corresponding plumbate(II) complexes are probably triligated also, but are labile on the nmr timescale; the parent complexes Pb(EPh)3 have been characterized in solution by (207)Pb and (13)C (E=S and Se) and (77)Se (E=Se) nmr spectroscopy.For both Pb(II) and Sn(II), the order of chemical shifts in the metal nmr spectra is δ(MSe3)>δ(MS3).The metal nmr spectra of the mixtures M(SePh)2:PhSe-:PhS ca. 1:2:4 (M=Sn(II) or Pb(II)) show that the coordination of PhSe- occurs in preference to coordination of PhS for both tin(II) and lead(II).Thiolatoplumbates(II) might be formed during some antidotal treatments for lead poisoning, so "fingerprint" (207)Pb nmr spectra have been measured for a range of model soluble species formed in Pb(SR)2-(excess)RS mixtures in MeOH, including some mixtures containing newly synthesized and characterized lead thiolates derived from dithiolate anions.For RS-=MeS-, EtS-, PhS-, C6H11S- (for which "Pb(SR)2" has been shown to be Pb(SC6H11)(OAc)), -S(CH2)2S-/2, -SCH2CHS-Me/2, and-SCH2CHS-CH2OH2, δPb (from PbMe4 in toluene as reference) falls in the comparatively short range 2518-2999 ppm.The redistribution of ligands between M(SPh)3 and M(SePh)3 in chloroform to give equilibrium mixtures of M(SPh)x(SePh)3-x occurs slowly on the preparative timescale for M=As, rapidly on the preparative timescale but slowly on the (13)C and (77)Se nmr timescales for M=Sb, and rapidly on the (13)C and (77)Se nmr timescales for M=Bi.Thus (13)C and, where appropriate (77)Se nmr data are reported for M(SPh)x(SePh)3-x (M=As orSb) and Bi(EPh)3 (E=S or Se).In addition, it has been possible, using (13)C nmr assessment of species distribution in the systems Sb(SPh)3 -As(SePh)3 and Bi(SPh)3-As(SePh)3, to deduce that for the trivalent Group V elements the order of preference for PhSe- over PhS- as ligands is Bi>Sb>As.Trends in the (13)C nmr data for M(SPh)x(SePh)3-x (M=As or Sb) and (77)Se nmr data for a range of metal complexes of PhSe- have been discussed.The selenium chemical shifts are influenced primarily by the acceptor atom and are in the order Cd(II)Zn(II)Pb(II)Sn(II)As(III)Bi(III)Sb(III).
