Volume 37, Issue 1-2

Six tin complexes of the type (O,N,N,O)Sn and (O,N,N,O)SnCl 2 ( L 1 Sn , L 2 Sn , L 3 Sn , L 1 SnCl 2 , L 2 SnCl 2 , L 3 SnCl 2 ) with di-anionic salen type tetradentate O,N,N,O chelators were synthesized and characterized by 1 H, 13 C, 119 Sn NMR spectroscopy, single-crystal X-ray diffraction, and elemental analysis ( L 1 Sn , L 2 Sn , L 1 SnCl 2 , L 2 SnCl 2 , L 3 SnCl 2 ) or 119 Sn solid state NMR spectroscopy and elemental analysis ( L 3 Sn ). The length of the oligomethylene bridge of the ligands (L 1 ) 2- , (L 2 ) 2- and (L 3 ) 2- (which are the anions of di-, tri- and tetramethylene-α,ω- N , N ′-bis(2-hydroxyacetophenoneimine, respectively) was found to have significant influence on the configuration of the tin coordination sphere. In detail, the Sn atom in L 1 Sn occupies the apex of a (O,N,N,O) square pyramid, whereas L 2 Sn resembles a see-saw setup of the tin coordination sphere, and L 3 Sn appears to be of oligomeric nature concluded from its distinctly lower solubility and different 119 Sn NMR shift. In the monomolecular Sn(IV) compounds the Cl atoms are trans -disposed in L 1 SnCl 2 , and cis -arrangements of the Cl atoms in combination with a mer - fac -arrangements of the (O,N,N,O) ligands are found in L 2 SnCl 2 and L 3 SnCl 2 .

The novel bimetallic adducts [(Ph 3 P) 2 CuCl] 2 .ZnCl 2 ( 1 ), {[(Me 3 P)CuCl] 2 .ZnCl 2 } n ( 2 ), [(Me 3 P) 4 Cu] + [(Me 3 P) 2 Cu(Cl) 2 ZnCl 2 ] - ( 3 ), (Ph 3 P) 2 CuCl.SnCl 2 ( 4 ), (Me 3 P) 3 CuSnCl 3 ( 5 ), [(Ph 3 P) 2 CuCl.SbCl 3 ] 2 ( 6 ) and (Ph 3 P) 3 CuCl.SbCl 3 ( 7 ) have been synthesized from combinations of R 3 P, CuCl and one of ZnCl 2 , SnCl 2 or SbCl 3 , and their structures were determined. [(Me 3 P) 2 Cu] + [HPMe 3 ] 2 + [Sb 2 Cl 9 ] 3- ( 8 ) and [(Me 3 P) 4 Cu] + [(Me 3 P) 2 Sb 2 Cl 7 ] - ( 9 ) have been isolated as minor by-products from the reaction of Me 3 P, CuCl and SbCl 3 , and their structures were also determined.

New complexes of dibutyltin(IV) of fluorinated β-diketones/benzoylacetone and sterically demanding heterocyclic β-diketones having the general formula Bu 2 SnLL′ (where LH=RCOCH 2 COR′, R=-C 6 H 5 , R′=-CF 3 ,L 1 H; R=-C 4 H 3 S, R′=-CF 3, L 2 H; R=-C 6 H 5 , R′=-CH 3 ,L 3 H and R″=-C 6 H 5 , L 1 ′H; R″=-p-ClC 6 H 4 , L 2 ′H; R″=-CH 3 , L 3 ′H and R″=-C 2 H 5 , L 4 ′H) were synthesized by the reaction of dibutyltin(IV)dichloride with sodium salts of fluorinated β-diketones/benzoylacetone and sterically demanding heterocyclic β-diketones in 1:1:1 molar ratios in refluxing dry benzene solution. Plausible structures of these Bu 2 Sn(IV) complexes were suggested on the basis of physico-chemical and spectral [infrared and nuclear magnetic resonance (NMR)] studies. 119 Sn NMR spectroscopic studies of some of these complexes revealed the presence of hexacoordinated tin centers.

The reaction of bis(cyclohexylammonium) 4-nitrophenylphosphate with Me 3 SnCl (1:2) under reflux in ethanol yielded the title compound 4-NO 2 C 6 H 4 PO 4 (SnMe 3 ) 2 ·H 2 O ( 1 ). The X-ray crystallographic analysis achieved on single crystals obtained by slow evaporation at room temperature revealed the formation of an unexpected supramolecular coordination network. The elementary building block can be viewed as two Me 3 Sn moieties linked by a bridging 4-nitrophenylphosphate ligand. The two tin atoms are five-coordinated and describe a trans -Me 3 SnO 2 geometry in a trigonal bipyramidal arrangement. However, the Sn atoms are distinct, exhibiting two different environments. Thus, one is linked to two axial oxygen atoms from two distinct phosphato groups, whereas the other is bound to one phosphato oxygen atom and to a water molecule. From a supramolecular point of view, the combination of the tridentate binding mode of 4-NO 2 C 6 H 4 PO 4 and the additional formation of intermolecular hydrogen bonding interactions between NO 2 /H 2 O and PO 4 /H 2 O groups gives rise to a three-dimensional lattice network.

Novel mixed ligand complexes containing thiophene-2-carboxylic acid (HTCA) and imidazole (im) ligands, [M(TCA) 2 (H 2 O) 2 (im) 2 ] (M: Mn, Co, Cd) and [Cu(TCA) 2 (im) 2 ] were obtained. The complexes were characterized by X-ray single crystal diffraction. Also, spectroscopic (IR and UV-Vis), magnetic and thermal properties were investigated. The thiophene-2-carboxylate acted in a monoanionic monodentate manner and bonded to the metals via its carboxylate oxygen. The im ligands bonded to the metals via hydrogen free nitrogen atoms. The geometry around the metal centers was octahedral [MO 4 N 2 ] for Mn(II), Co(II) and Cd(II) complexes and square-planar [CuO 2 N 2 ] for the Cu(II) complex. Due to intermolecular interactions in the solid state, the Co(II), Mn(II) and Cd(II) complexes showed three-dimensional networks, while the copper complex was a one-dimensional network. In consideration of the anhydrous form of the complexes, the thermal stability of the complexes was of the following order: Co (273°C)>Cu (229°C)>Cd (175°C)>Mn (167°C).

The preparation, via transmetallation reaction of an appropriate lithium precursor and a tin(II)-containing compound, spectral properties ( 1 H and 119 Sn NMR spectroscopy) and structure of the tin(II) complex [DippNC( n Bu)NDipp]Sn{ p Tol-NC[N(SiMe 3 ) 2 ]N- p Tol} containing both amidinato and guanidinato ligands is reported.