I. N. Meshcheryakova

The new C–C bond formation in the reaction of o-amidophenolate indium(III) complex with alkyl iodides

The reaction of bis(4,6-di-tert-butyl-N-(2,6-di-iso-propylphenyl)-o-amidophenolato)indium(III) anion with alkyl iodides is reported. This process includes oxidative addition of two RI (R = Me, Et) molecules to the non-transition metal complex and results in an alkyl transfer to ring carbon atoms with the formation of two new C-C bonds. The interaction proceeds at mild conditions and gives new indium(III) derivatives containing iminocyclohexa-1,4-dienolate type ligands.

The reactivity of o-amidophenolate indium(III) complexes towards different oxidants

The reactivity of o-amidophenolate indium(III) complexes towards different oxidants was investigated. The oxidation reactions were found to proceed through the stage of paramagnetic o-iminobenzosemiquinonato indium(III) derivative formation. The monoradical intermediates undergo symmetrization. The final products of the oxidation processes are corresponding biradical o-iminobenzosemiquinonato indium(III) complexes. In order to understand the reasons for the symmetrization processes steric factors (G-parameters) were evaluated for all intermediates and final products by a method based on the ligand solid angle approach.

Tin(IV) complexes based on 2-hydroxy-3,6-di-tert-butyl-para-benzoquinone: Syntheses, structures, and electrochemical behavior in solution

A series of new tin(IV) complexes based on 2-hydroxy-3,6-di-tert-butyl-para-benzoquinone (LH) of the general formula L2SnR2 (R = Me (I), Et (II), Bun (III), Ph (IV)) and LSnMe3 (V) were synthesized. The obtained compounds were characterized by IR and 1H, 13C and 119Sn NMR spectroscopy and elemental analysis. The X-ray diffraction analysis was carried out for complexes L2Sn(Bun)2 (III) and LSnMe3 (V). The low-frequency region of the IR spectra, which has not earlier been studied in detail, was interpreted for compounds I–V and previously described complex LSnPh3 (VI). The electrochemical properties of LH and related tin complexes I–VI were studied. The nature of the hydrocarbon groups at the metal atom affects the stability of the intermediates formed in the electrochemical reactions.

o-Iminosemiquinone complex of tin(iv) with tert-butyl substituents in the polymer synthesis

Characteristic features of synthesis of various polymers with participation of the tin complex imSQSnBut2Cl, where imSQ is the 4,6-di-tert-butyl-N-(2,6-diisopropylphenyl)-o-iminobenzoquinone radical anion, were studied. It was shown that for a number of monomers, this complex acts as an iniferter, i.e., it can not only initiate the polymerization, but can also regulate the chain growth of macromolecules. The effect of the conditions of the process on the possibility of obtaining macromolecular products with a narrow polydispersity was estimated.

Redox reactions involving the indium(III) catecholate complexes

Indium catecholate complexes 3,6-CatInR (3,6-Cat is the 3,6-di-tert-butyl-o-benzoquinone dianion (3,6-Q), R = Me (I) and Et (II)) are synthesized by the exchange reaction between RInI2 and thallium catecholate 3,6-CatTl2. Compounds I and II are trimeric in both the solution and crystalline state. The oxidation of compound I and earlier described complex [3,6-CatInI(THF)]2 (THF is tetrahydrofuran) by various substrates (iodine, 3,6-Q, and tetramethylthiuram disulfide) is studied. Different indium(III) o-semiquinone complexes are the reaction products, depending on the reaction conditions.

Tin(IV) o-iminosemiquinone complex: An example of a new type of organometallic iniferter

ISSN 00125008, Doklady Chemistry, 2012, Vol. 447, Part 2, pp. 286–292.

Experimental and theoretical study of the vibrational spectra of tin(IV) complexes based on 2-hydroxy-3,6-di-tert-butyl-para-benzoquianone

Raman spectra of tin 2-hydroxy-3,6-di-tert-butyl-para-benzoquianone complexes L2SnX2 and LSnX3 (L is 2-oxy-3,6-di-tert-butyl-para-benzoquianone; X = CH3, C2H5, n-C4H9, and C6H5) are studied. A comparative analysis of the experimental and calculated spectra is carried out and the vibrational frequencies are conventionally assigned. A new tin(IV) complex based on 2,5-dihydroxy-3,6-di-tert-butyl-para-benzoquianone (L′H2) containing phenyl substituents at the metal atom is synthesized. Absorption bands of the complexes are interpreted in the low-frequency range of the infrared spectrum that was not considered previously.

Syntheses, structures, and electrochemical properties of the tin(IV) complexes based on the 2-hydroxy-4- N -(phenyl)-3,6-di- tert -butyl- p -iminobenzoquinone ligand

A series of the new tin(IV) complexes based on the 2-hydroxy-4-N-(phenyl)-3,6-di-tert-butyl-p-iminobenzoquinone ligand (LH) containing various hydrocarbon substituents R at the metal atom (R = Me, Et, nBu, tBu, and Ph) is synthesized. The structures of the synthesized compounds were determined by elemental analysis, IR spectroscopy, and 1H and 119Sn NMR spectroscopy. The X-ray diffraction analyses are carried out for the LSnPh3 (I) and L2SnEt2 (IV) complexes (CIF files CCDC no. 1557840 (I) and 1557839 (IV)). The main electrochemical characteristics in a solution are obtained for the whole series by cyclic voltammetry.

Stable organomercury compounds containing an o-iminosemiquinone radical ligand

A series of stable paramagnetic organomercury compounds containing the 4,6-di-tert-butyl-N-(2,6-diisopropylphenyl)-o-iminobenzosemiquinone ligand (imSQ) with the general formula imSQHgR (R = Ph, Et, Prn, Bun, Pri, Hexc, CH2SiMe3, p-FPh, Fc, p-Me2NPh) were synthesized. The molecular and electronic structures of the synthesized compounds were investigated by EPR spectroscopy and X-ray diffraction. The o-iminosemiquinone ligand shows the unusual amidophenoxy-type coordination mode. In the EPR spectra of the compounds imSQHgR, the hyperfine coupling constant of magnetic mercury isotopes (199,201Hg) depends on the nature of the substituent R, the temperature, and the nature of the solvent. Voltammetric investigations showed that the complex imSQHgFc undergoes three reversible one-electron redox steps related to the redox transformations of both the o-iminoquinone ligand and the metallocene moiety of the molecule.