Synthesis and multinuclear magnetic resonance study of some tin(IV) complexes of pyridine-2-thiolate and related ligands, and the X-ray structural analysis of Sn(C₅H₄NS)₄•C₅H₅NS

Abstract

. Tin metal reacts with 2,2'-dithiobis (pyridine) in refluxing toluene to give the pyridine-2-thiolate complex Sn(C5H4NS)4, l a . Multinuclear ( 7 7~e , '''sn) magnetic resonance shows that ligand redistribution occurs in l~: s n ( E P h )~ (E = S or Se) mixtures to give Sn(EPh)4-,(C5H4NS)x. From the pattern of the "'~n chemical shifts of these series, compared with that of Sn(EPh),-,(SR), (R = simple alkyl or aryl group), the complexes are shown to be five-coordinate Sn(EPh)3(C5H4NS-N,S) when x = 1 and six-coordinate Sn(EPh)4-x(C4H4NS-S)x-2(C5H4NS-N,S)2 when x = 2-4. Reaction of Sn(SPh)' and (C5H&!S)2 yields pure Sn(SPh)2(C5H4NS)2. The 13C NMR spectrum of Sn(C5H4NS-S)2 (C5H4NS-N,S)' is an exchange average down to 178 K, probably as a result of fluxionality. The series Sn(EPh)4-x(L')x (E = Se, L' = 5-nitropyridine-or quinoline-2-thiolate, x = 0-4; E = S or Se, L' = pyridine-2-thiolate-N-oxide, x = 0-2) can beprepared insitu by redox between Sn(EPh)4 and the disulfide (L1)'. Treatment of l a with X2 (X = Br or E-gives SnX4-,(C5H4NS-N,S), (x = 2 or 3), which have been characterized by NMR, and provides a new synthesis of the known dihalo complexes.In a recrystallization of l a from CH2C12:hexane Sn(C5H4NS)4.CsH5NS, 2, was obtained, probably as a result of hydrolysis. The structure of 2 has been solved by single crystal X-ray diffraction techniques. The compound crystallizes in the orthorhombic space group Pbca (No. 61) with a unit cell of dimensions a = 17.132 (2) L'Ctain mitallique rCagit avec la 2,2'-dithiobis (pyridine), dans le tolukne au reflux, pour donner le complexe pyridine-2-thiolate, Sn(C5H4NS)4, l a . La rtsonance magnktique multi-noyaux ( 7 7~e , "'~n) dCmontre que, dans des mClanges de l a : Sn(EPh)4 oh E = S ou Se, il se produit une redistribution des ligands et la formation de composts du type Sn(EPh)4-,(C5H4NS)x. En se basant sur une comparaison des dtplacements chimiques du "' Sn dans les composCs de cette strie avec ceux obsewks dans les produits Sn(EPh),-,(SR), ou R = groupements aryles ou alkyles simples, on a dCmontrC que, si x = I, les complexes sont les entitCs penta-coordonnCes Sn(EPh)3(C5H4NS-N,S) alors que, si x = 2-4, les complexes sont les entitks hexa-coordonn6es Sn(EPh)4-X(C5H4NS-S)2. La reaction du Sn(SPh)' avec le (C5H$JS)2 fournit du Sn(SPh)2(C5HflS)2 a 1'Ctat pur. M&me lorsqu'on abaisse la tempkrature jusqu'i 178 K, le spectre rmn du 13C du Sn(C5H4NS-S)2(C5H4NS-N,S)2 est un spectre moyen rCsultant probablement d'un mtcanisme de fluxion. Faisant appel a une rCaction redox in situ entre l e Sn(EPh)4, et le disulfure (L1)', on peut prCparer les produits de la sCrie Sn(EPh)4-,(L')x (E = Se, L' = 5-nitropyridine-ou quinolkine-2-thiolate, x = 0-4; E = S ou Se, ' L' = pyridine-2-thiolate N-oxyde, x = 0-2). Le traitement du produit l a par du X2 (X = Br ou I) fournit les complexes SnX4-,(C5H4NS-N,S), (x = 2 ou 3) que I'on a caractCrists par rmn; ces rkactions fournissent une nouvelle synthkse de ces complexes dihalogCnCs connus.Lors de la recristallisation du produit l a dans un mClange...

Synthesis, characterisation and X-ray structures of diorganotin(IV) and iron(III) complexes of dianionic terdentate Schiff base ligands

“…The spectra of the complexes show a singlet at À188.4 and À195.5 ppm for 1 and 3, respectively, and at À332.9 and À357.8 ppm for 2 and 4, respectively. It is well known that 119 Sn chemical shifts are very sensitive to changes in the coordination number of tin and to the nature of the groups directly attached to the tin atom [20]. The chemical shifts for the complexes reported here are within the expected range for dimethyland diphenyltin(IV) complexes with a coordination number of five [21].…”

Pyridine-2-selenolate and -2-tellurolate as ligands: a multinuclear (77Se, 119Sn, 125Te) magnetic resonance study of some tin(IV) complexes, and X-ray structural analyses of Sn(SPh)2(2-Se-C5H4N-N,Se)2 and Sn(SPh)1.85(2-Se-C5H4N)2.15

“…Proton and 13c NMR data obtained for this compound are consistent with those reported (13) while our work was in progress. 4 All solvents for use in NMR sample preparation or synthesis were dried over 3A molecular sieves and sparged with Ar(g) before use.…”

“…These complexes were prepared in solution using methods described earlier for tin(1V) complexes of pyt-and its N-oxide (4). The tin complexes comprise a model system in which information from the 7 7~e / 1 2 5~e NMR chemical shifts is bolstered by both Il9sn NMR chemical shifts and one-bond coupling between 119'117~n and 7 7~e / 1 2 5~e .…”

Synthesis and characterization of a new chloro-di-phenyltin(IV) complex with 2-mercapto-nicotinic acid: Study of its influence upon the catalytic oxidation of linoleic acid to hydroperoxylinoleic acid by the enzyme lipoxygenase

“…following requirements: (i) to have available coordination positions around Sn and (ii) to have a relatively stable ligand-Sn bond (e.g., Sn-N and Sn-S) with low hydrolytic decomposition [7]. Organotin(IV) complexes with thioamides have also been synthesized and studied for their anti-tumor activity [8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27]. We recently studied the synthesis, structural characterization and in vitro cytotoxicity of organotin(IV) derivatives of the heterocyclic thioamides, 2-mercaptobenzothiazole, 5-chloro-2-mercaptobenzothiazole, 3-methyl-2-mercaptobenzothiazole and 2-mercaptonicotinic acid [5a,5b].…”