Semicarbazones and thiosemicarbazones

Bonding and structure trends of thiosemicarbazone derivatives of metals—An overview

“…The substitution of CO by a thiosemicarbazone in W(CO) 6 yielded W(CO) 5 (HL) 20 [80] and 21 [81] (Chart 4). The neutral ligands coordinate via the S-donor atom only; the W C bond distance trans to S is shorter than the other W C distances, due to the better acceptor properties of CO vis-à-vis that of Sdonor atom.…”

“…For W, Tc and Re complexes, metal carbonyls, W(CO) 6 [80,81], (NEt 4 ) 2 Tc(CO) 3 Cl 3 [82], and ReX(CO) 3 (CH 3 CN) 2 [83,84], have been used as precursors. For example, tungsten complexes were prepared by the reaction of a thiosemicarbazone with W(CO) 6 in presence of trimethyl amine-N-oxide in acetone [80,81]. Further, some Re complexes were prepared using [ReOCl 3 (Ph 3 P) 2 ] [85].…”

“…For molybdenum, MoO 2 (acac) 2 is used as a starting material, the acac anion is replaced by the thiosemicarbazone ligand during complexation [77][78][79]. For W, Tc and Re complexes, metal carbonyls, W(CO) 6 [80,81], (NEt 4 ) 2 Tc(CO) 3 Cl 3 [82], and ReX(CO) 3 (CH 3 CN) 2 [83,84], have been used as precursors. For example, tungsten complexes were prepared by the reaction of a thiosemicarbazone with W(CO) 6 in presence of trimethyl amine-N-oxide in acetone [80,81].…”

The Influence of the Methyl Substituents at C2 Carbon of Thiosemicarbazones {R1R2C2=N3‐N2H‐C1(=S)N1H2} on Bonding and Structures of Copper(I) Complexes

“…Thiosemicarbazone chemistry of copper(I) has received attention only recently [11Ϫ13], unlike copper(II) which has been intensively investigated [1Ϫ4]. For R 1 ϭ pyridyl, R 2 ϭ H, and R 1 ϭ R 2 ϭ Ph, only tetrahedral monomers [CuX(Htsc)(PPh 3 ) 2 ] (X ϭ Cl, Br, I), for R 1 ϭ Ph, R 2 ϭ H,both monomers (X ϭ I) and dimers (X ϭ Br, Cl), and for R 1 ϭ furan, thiophene and pyrrole, R 2 ϭ H, both halogen bridged [Cu 2 (µ-I) 2 (η 1 -S-Htsc) 2 (PPh 3 ) 2 ] and sulfur bridged dimers [Cu 2 (µ-S-Htsc) 2 X 2 (PPh 3 ) 2 ] (X ϭ Br, Cl) have been isolated [12,13].Further, acetone thiosemicarbazone (R 1 ϭ R 2 ϭ Me) with copper(I) chloride has formed a tetramer [Cu 4 (Htsc) 4 Cl 4 ], and a monomer [Cu(Htsc) 2 ]Cl [11], along with its complexes with other metals [14].…”

Pentacarbonyl(imidazolidine-2-thione-κS)tungsten(0)

“…For hydrogen-bond motifs, see: Etter et al (1990); Bernstein et al (1995); Beheshti et al (2007). For related structures, see: Kuhn et al (1998); Mak et al (1985); Valdé s-Martinez et al (1988; Pasynsky et al (2007); Darensbourg et al (1999).…”