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Konstantin A. Kozhanov Michael P. Bubnov Nina N. Vavilina Larisa Yu. Efremova Georgy K. Fukin Vladimir K. Cherkasov Gleb A. Abakumov 《Polyhedron》2009,28(13):2555-2558
Structural study of dialkyl (PCP)-pincer o-semiquinonato nickel complexes indicated sloped relative positions of bi- and tri-dentate ligands. It became bright confirmation of propositions made on the base of their EPR spectra followed by molecular modelling. 相似文献
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Andrey I. Poddel’sky Ivan V. Smolyaninov Georgy K. Fukin Vladimir K. Cherkasov 《Journal of organometallic chemistry》2010,695(8):1215-8281
Novel functionalized triphenylantimony(V) catecholates - Ph3Sb[4-O(CH2CH2)2N-3,6-DBCat] (1), Ph3Sb[4-PhN(CH2CH2)2N-3,6-DBCat] (2), Ph3Sb[4-Ph2CHN(CH2CH2)2N-3,6-DBCat] (3), Ph3Sb[4,5-Piperaz-3,6-DBCat] (4) and binuclear bis-catecholate Ph3Sb[3,6-DBCat-4-N(CH2CH2)2N-4-3,6-DBCat]SbPh3 (5) were synthesized by the oxidative addition reaction of corresponding o-quinones with triphenylantimony. The [4-O(CH2CH2)2N-3,6-DBCat]2−, [4-PhN(CH2CH2)2N-3,6-DBCat]2−, [4-Ph2CHN(CH2CH2)2N-3,6-DBCat]2− and [4,5-Piperaz-3,6-DBCat]2− are 4-(morpholin-1-yl)-, 4-(4-phenyl-piperazin-1-yl)-, 4-(4-dephenylmethyl-piperazin-1-yl)-, and 4,5-(piperazin-1,4-diyl)-3,6-di-tert-butyl-catecholate dianionic ligands, correspondingly. Complexes 1-5 were characterized in details by IR-, 1H and 13C NMR spectroscopy and cyclic voltammometry. Molecular structure of 4·CH3OH was determined by X-ray crystallography to be a distorted tetragonal-pyramidal. The NMR spectroscopic and electrochemical investigations of complexes in the presence of air reveal the reactions of complexes with dioxygen leading to the formation of spiroendoperoxides of 1,2,4,3-trioxastibolane type in a NMR yield of 25-37%. 相似文献
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A. I. Poddel’sky M. V. Arsen’ev L. S. Okhlopkova I. V. Smolyaninov G. K. Fukin 《Russian Journal of Coordination Chemistry》2017,43(12):843-851
The following new triphenylantimony(V) catecholate complexes bearing the protonated imine group are synthesized from the new sterically hindered 3,5-di-tert-butylpyrocatechols (6-(CH=N-o-(C6H4–NH2))-3,5-Cat)H2 (H2L1) and (6-(CH=N-o-(C6H4–OH))-3,5-Cat)H2 (H2L2) containing in position 6 the iminomethyl group bonded to the aniline or phenol substituent: (6-(CH=NH+-o-(C6H4–NH2))-3,5-Cat)SbPh3X (X = Br (I), OMe (III)) and (6-(CH=NH+-o-(C6H4–OH))-3,5-Cat)SbPh3X (X = Br (II), OMe (IV)). The molecular structure of complex III · CH 3 OH in the crystalline state is determined by X-ray diffraction analysis (CIF file CCDC no. 1554694). The electrochemical properties of complexes III and IV are studied by cyclic voltammetry. 相似文献
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N. Yu. Grishina E. V. Sazonova A. N. Artemov G. K. Fukin V. I. Faerman 《Russian Chemical Bulletin》2017,66(2):313-319
The reactions of 1,3-dipolar cycloaddition of π-complexes of nitrones of a general formula R2CH=N(O)R1, where R1 = Me, But, Ph, R2 = Ph[Cr(CO)3], C5H4[Mn(CO)3] with (η6-styrene)-tricarbonylchromium and vinyl-(η5-cyclopentadienyl)tricarbonylmanganese have been investigated. These reactions led to the formation of corresponding isoxazolidines with high regio- and diastereoselectivity. The obtained metal-containing isoxazolidines were identified using UV, IR, 1H NMR spectroscopy, mass-spectrometry, and X-ray diffraction analysis. 相似文献
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V. Yu. Rad��kov G. G. Skvortsov G. K. Fukin K. A. Lyssenko M. Yu. Antipin A. A. Trifonov 《Russian Chemical Bulletin》2011,60(5):803-808
The reaction of lithium silylamide [??o-MeOC6H4N(SiMe3)}Li(OEt2)]2 with 2 equiv. of benzonitrile in THF at ??20 °C affords the lithium derivative of the new tridentate amidinate ligand [{o-MeOC6H4NC(Ph)N(SiMe3)}Li]2. The X-ray diffraction study showed that this complex has a dimeric structure due to the coordination of the N atoms and the ether group of one amidinate ligand to different Li atoms. The reaction of anhydrous YCl3 with the resulting complex in THF gives the monoamidinate complex [{o-MeOC6H4NC(Ph)N(SiMe3)}YCl2(THF)2]2 regardless of the reagent ratio. The latter has a dimeric structure in the crystalline state as a result of the presence of two ??2-bridging Cl atoms that link Y atoms. The ether groups of the amidinate ligands are not involved in the metal-ligand interaction. 相似文献
29.
M. E. Burin A. A. Logunov N. O. Druzhkov G. K. Fukin M. N. Bochkarev 《Russian Chemical Bulletin》2011,60(8):1586-1590
Neodymium diiodide hydride under mild conditions adds at the carbonyl group of benzophenone to give (diphenylmethoxy)(diiodo)neodymium(iii) of the formula I2Nd(OCHPh2)(THF)4. In reactions of NdI2H and DyI2H with N-(2,6-diisopropylphenyl)-9,10-phenanthrenequinonimine, the system of conjugated C=N and C=O groups of the quinone is reduced. The resulting o-aminophenanthrolate complexes are structurally characterized by X-ray diffraction. 相似文献
30.
M. P. Shurygina N. O. Druzhkov M. V. Arsen’ev M. P. Bubnov G. K. Fukin S. A. Chesnokov V. K. Cherkasov 《Russian Journal of Organic Chemistry》2011,47(4):486-495
Alkoxylation of 3,6-di-tert-butyl-1,2-benzoquinone with a number of diols, including propane-1,3-diol, butane-1,4-diol, di-, and triethylene glycols,
and cyclohexane-1,4-diyldimethanol, was studied. Nine new 4-alkoxy-3,6-di-tert-butyl-1,2-benzoquinones were synthesized, four of which were bis-1,2-benzoquinones with different tethers (6–13 atoms) between
the quinone fragments. Depending on the length of the chain between the hydroxy groups in glycols, bicyclic 4,5-disubstituted
3,6-di-tert-butyl-1,2-benzoquinones were formed or their stepwise alkoxylation occurred. The newly synthesized o-benzoquinone derivatives can be reduced with alkali metals to give radical anions and converted into semiquinone chelates
with manganese carbonyl. 相似文献