Chelate von β‐Diketonderivaten. IV. Synthese, Eigenschaften und spektroskopische Daten Isomerer β‐Thioxoketone und ihrer Nickel(II)‐chelate

Abstract

InhaltsubersichtEs wird uber die Synthese einer Reihe einfacher und unsymrtietrisch substitxiierter isomerer ,k?-Thioxoketone und ihrer Ni(l1)-Chclate berichtet.Die Elektronenspektren der Liganden im Bereich yon 250 bis 700 mp und ihre II1-Spektren zwischen 400 und 3800 cm-l sowie die optischen Spcktren der Ni(I1)-Chelate werden beschrieben. Bei den isomeren b-Thioxoketonen werden die regelmaBigen Eigenschaftsanderungenwie Farbe und Schmelzpunkte der Liganden mid ihrer Ni(I1)-Chelate, Elektronenund IR-Spektrenin Abhangigkeit von dem in Nachbarschaft zum Carbonylschwefel befindlichen Substituenten diskutiert. 0 S S 0 1) 111. Mitteilung: G . KLOSE, PH. THOMAS u. E. UHLEMANN, Tetrahedron (im Druck).

Bismuth(iii) β-thioxoketonates as antibiotics against Helicobacter pylori and as anti-leishmanial agents

“…Both transition metal; Ni(II), Co(III), Fe(III), Zn(II), Cu(II), Pt(II), Pd(II) and Mo(VI), [19][20][21][22][23] and p-block metal β-thioxoketonates, Sn(IV), In(III), Ga(III), Ge(IV), have been reported. 24,25 The β-thioxoketonato ligands predominantly bind to the metal centre in a bidentate fashion through the O and S atoms, the exception being Ge(IV) in which the ligand binds only through the S atom.…”

Di[2-(4-substituted-phenyl)-3-mercapto-propenato]-nickel(II) complexes. Metallo-mesogens exhibiting broad nematic ranges

“…In our search for suitable ligands, we noticed, that monothio-b-diketones have not been taken into consideration for this purpose until now, although they form very stable square planar nickel(I1) chelates [7,8]. The synthetic route we chose is shown in figure 1 and corresponds to a literature method [9] for similar monothio-ketones.…”

.beta.-Thioxo ketones. 2. Preparation and structure of some five- and six-membered 2-acylcycloalkanethiones and 2-thioacylcycloalkanones

“…Structure. The NMR spectrum of 2-acetylcyclohexanethione (1) (Figure 1) shows the pattern of a single component, just as in the case of thioacetylacetone.1 If this spectrum is interpreted in terms of the existence of a very fast tautomeric interchange between merely the forms 1C and ID, the observed weighted average chemical shift of the chelate proton (6 6.63 ppm at infinite dilution8) clearly reflects a preponderant contribution of 1C. For comparison, the mercapto proton signal of 2-ethoxycarbonyl-l-mercaptocyclohexene is found at 5.23 ppm,9 whereas the hydroxyl proton signal of enolic 2-ethoxycarbonylcyclohexanone is found at 12.12 ppm,10 and the chemical shift of the chelated hydroxyl proton of enolic nonaromatic /3-diketones in general has a value between 13 and 18 ppm11•12 ( 15.90 ppm for enolic 2-acetylcyclohexanone12).…”

“…These bands were assigned to -* transitions in the SC=CC=0 chromophore (the enethiol tautomer C) and in the OC=CC=S " Measured on CCI4 solutions. 6 Tentative assignment, made by comparison with the IR spectrum of thioacetylacetone.1 This band was absent in the IR spectra of 1 and 2-acetylcyclohexanone.…”