Two new Pb coordination polymers derived from pyrimidine-2-thiolate: Synthesis, methyl substitution-induced effect and properties

One- and two-dimensional PbII compounds resulting from reaction of PbBr2 and Pb(SCN)2 with pyrimidine-2-thione

“…lengths range from 2.72 to 2.73 Å (Schwade et al, 2015;Song et al, 2016). When compared with free HSpym in its thione form (S-C bond length of 1.68 Å ) (Owczarzak et al, 2013), the elongation of the S-C bond to 1.729 (2) Å in compound (I) reflects the coordination through the S atom which is indicative of deprotonation.…”

“…S2 in the supporting information). The final residue of PbS is probably formed at higher temperatures, as proposed for the decomposition of [Pb(Spym) 2 ] n under a nitrogen atmosphere (Song et al, 2016). Bulk PbS is a semiconductor with a small band gap (0.41 eV), making it interesting for applications such as in nonlinear optics (Saraidarov et al, 2004).…”

“…5a), with a distance of 3.599 (7) Å . The S1-C1 bond length of 1.713 (6) Å in HSpym is shorter than the S-C bond lengths in [Pb II (Spym) 2 ] n [range 1.720 (6)-1.730 (5) Å ] (Schwade et al, 2015;Song et al, 2016). Compared with free HSpym in its thione form, with a C S bond length of 1.68 Å (Owczarzak et al, 2013), the C-S bond in compound (IIa) is intermediate between single-and double-bond character.…”

“…1371 cm À1 corresponds to their asymmetric stretching (Song et al, 2016). In free HSpym, C N vibration bands appear at 1608 and 1568 cm À1 .…”

“…The coordination of anionic pyrimidine-2-thiolate (Spym À ) with Pb produces polymeric [Pb(Spym) 2 ] n coordination compounds. A one-dimensional (1D) ribbon structure (Song et al, 2016) and a three-dimensional (3D) metal-organic polymer (Schwade et al, 2015) have been reported. These compounds were obtained by reaction of HSpym and lead(II) acetate under solvothermal conditions, or by conventional synthesis using triethylamine, respectively.…”