Volume 35, Issue 1-2

This review summarizes almost 40 structures of polymeric Fe(M), where M=Mg, Ca, Sr, Ba, In, Te, Ge, Sn, Bi, Zn, Cd and Hg complexes. The complexes crystallized in the monoclinic, tetragonal, orthorhombic and triclinic classes, from which the monoclinic by far prevails (∼50%). The most common ligands are with O, N and C donor atoms. The iron atoms are found in the oxidation states 0, +2 and +3, with +3 being the most common. In most complexes the iron(0) is 5-, iron(II) and iron(III) are 6-coordinated, but there are examples of 3-, 5- and even 7-coordinated complexes. The inner coordination spheres about the M atoms range from 3 to 11. The structures are discussed in terms of the coordination about the metal atoms, and correlations are outlined between donor atoms, bond lengths and interbond angles.

Three series of methoxyphenyl substituted β -diketiminate and β -enaminoketonate and chlorophenyl β -enaminoketonate ligands were prepared and studied by IR, 1 H and 13 C NMR spectroscopy in solution and X-ray diffraction techniques in solid state. The crystal structures of [2-(MeO)C 6 H 4 ]N=(H)-CCH(H)C[2-(MeO)C 6 H 4 ]NH.HCl,[2-(MeO)C 6 H 4 ]N=(H)CCH(H)C[2-(MeO)C 6 H 4 ]NH, [4-(MeO)C 6 H 4 ]N=(H)CCH-(H)C[4-(MeO)C 6 H 4 ]NH, [4-ClC 6 H 4 ]N(H)(Me)CCH(Me)C=O, [2-(MeO)C 6 H 4 ]N=(Me)CCH(Me)C[2-(MeO)C 6 H 4 ]NH and 7-methoxy-2,4-dimethylquinoline-toluenesulfonylacid adduct as ligands, their precursors and a byproduct isolated during the synthesis of [3-(MeO)C 6 H 4 ]N(H)(Me)CCH(Me)C=O were determined. One of the ligands the meta -methoxyphenyl substituted β -enaminone has been treated with n -butyllithium to give {[3-ClC 6 H 4 ]N(Me)CCH(Me)C=O}Li which reveals tetrameric structure in the solid state. Further reactions of this lithium complex with tri- and diorganotin(IV) chlorides and hydride give appropriate organotin(IV) complexes with five coordinated tin atom. The direct reaction of bis( para -methoxyphenyl) substituted β -diketimine with Sn[N(SiMe 3 ) 2 ] 2 gives [4-(MeO)C 6 H 4 ]N=(H)CCH(H)C[4-(MeO)C 6 H 4 ]NSnN(SiMe 3 ) 2 . Structure of these complexes was evaluated by 1 H, 7 Li and 119 Sn NMR spectroscopy and X-ray diffraction analysis for two examples.

The reaction of 8-Me 2 NC 10 H 6 Li·Et 2 O with InCl 3 and TlCl, respectively, followed by work-up under aerobic conditions, provided the intramolecularly coordinated diarylelement chlorides [(8-Me 2 NC 10 H 6 ) 2 E]Cl ( 1 , E=In; 2 , E=Tl) in reasonable yields. Single crystal X-ray structure analyses of 1 and 2 revealed that both compounds essentially contain centrosymmetric dimers of [(8-Me 2 NC 10 H 6 ) 2 E] + cations (E=In, Tl) that are loosely associated by the chloride ions.

The synthesis of heteroleptic zinc amidinate complexes is reported. Reactions of LZnI [L= t -BuC(NDipp) 2 ; Dipp=2,6- i -Pr 2 -C 6 H 3 ] with diisopropylcarbodiimide ( i -PrN) 2 C yielded the Lewis acid-base adduct LZn(I)-N( i -Pr)CN( i -Pr) 1 . In addition, the synthesis of LZnN(SiMe 3 ) 2 2 and its reaction with ( i -PrN) 2 C, which occurred with formation of the heteroleptic amidinate-guanidinate complex LZnL′ 3 [L′=(Me 3 Si) 2 NC(N i -Pr) 2 ], is reported. Compounds 1 – 3 were characterized by nuclear magnetic resonance ( 1 H, 13 C) and infrared spectro\xadscopy, elemental analysis, and single crystal X-ray diffraction ( 1 and 2 ), respectively.

The reaction of the silanes X 2 SiCl 2 (X=H, Cl) with the dilithium salts of N -phenyldiethanolamine ( 1 ) and N -4-fluorophenyl-di-(2-dimethylpropan-2-ol)amine ( 2 ), respectively, gave the novel 5-aza-2,8-dioxasilabicyclo[3.3.0 1.5 ]octanes RN(CH 2 CR′ 2 O) 2 SiX 2 ( 3 , R=Ph, R′=X=H; 4 , R=Ph, R′=H, X=Cl; 5 , R=4-FC 6 H 4 , R′=Me, X=H). These compounds were characterized by multinuclear NMR spectroscopy and single crystal X-ray diffraction analysis ( 1–4 ). The molecular structures of the dialkanolamines 1 and 2 are characterized by intra- and intermolecular O-H ··· O(H) hydrogen bridges giving rise to formation of eight-membered O 4 H 4 rings ( 1 ) and polymeric chains ( 2 ). The 5-aza-2,8-dioxasilabicyclo[3.3.0 1.5 ]octanes show intramolecular N→Si interactions at distances of 2.961(2) ( 3 ) and 2.970(2) ( 4 ) Å, respectively. Also reported is the molecular structure of the hexachloridostannate salt [Ph(H)N(CH 2 CH 2 OH) 2 ] 2 SnCl 6 ( 6a ) that was serendipitously obtained from the reaction of compound 3 with Ph 3 CSnCl 5 under non-inert reaction conditions. Furthermore, DFT calculations on 3 and 4 as well as cyclovoltammetric studies were performed.

Zn(thqdtc) 2 (TMEDA) ( 1 ), Cd(thqdtc) 2 (TMEDA) ( 2 ), Zn(2-mpipdtc) 2 (TMEDA) ( 3 ), and Cd(2-mpipdtc) 2 (TMEDA) ( 4 ) (where thqdtc=1,2,3,4-tetrahydroquinolinedithiocarbamate, 2-mpipdtc=2-methylpiperidinedithiocarbamate,and TMEDA= N , N , N ′, N ′-tetramethylethylenediamine) have been synthesized and characterized by infrared (IR) and nuclear magnetic resonance ( 1 H and 13 C) spectra. A single crystal X-ray structural analysis was carried out for complex 2 . IR spectra of the complexes show the contribution of the thioureide form to the structures. The N 13 CS 2 chemical shifts of Zn(dtc) 2 (TMEDA) are additionally deshielded compared with Zn(dtc) 2 (dtc=thqdtc, 2-mpipdtc) owing to the increase in coordination number. Single crystal X-ray structure analysis of 2 showed that cadmium is in a distorted octahedral environment with a CdS 4 N 2 chromophore. The acceptance of an additional neutral ligand by the tetrahedral dithiocarbamato complex of cadmium to form an octahedral adduct causes an increase in the Cd-S bond lengths.

The crystal and molecular structure of [Cy 2 NH 2 ] 2 [C 6 H 3 (CO 2 ) 3 SnMe 3 ·H 2 O]·CH 3 CH 2 OH ( 1 ) has been determined by single crystal X-ray diffraction analysis. In this compound, the tin atom is pentacoordinated by three methyl groups, one oxygen atom of a water molecule and one oxygen atom deriving from the tris-carboxylato ligand, in a trans -coordinated O 2 SnC 3 environment. The dicyclohexylammonium cations are involved in intermolecular hydrogen bonds with the non-coordinated oxygen atoms of the carboxylate, while, along with hydrogen bonds involving water and ethanol, gives rise to a complex 3D lattice structure.

The title compound Bu 2 NH 2 (PhPO 3 H) 2 SnMe 3 was synthesized and its structure determined by single crystal X-ray crystallography. The structure consists of two monodentate hydrogenophosphonates [PhPO 3 H] - bonded to SnMe 3 groups leading to SnC 3 O 2 moiety in a trans trigonal bipyramidal environment. [(PhPO 3 H) 2 SnMe 3 ] - dimerizes through hydrogen bonds. Dibutylammonium (Bu 2 NH 2 + ) cations are hydrogen bonded to the dimeric moieties through phosphonates to give a chain structure.

No abstract available.