4810-09-7Relevant academic research and scientific papers
SYNTHESIS AND CONVERSIONS OF METALLOCYCLES. 8. REGIOSELECTIVE β-HYDROXYVINYLATION OF α-OLEFINS WITH THE PARTICIPATION OF METALLCOMPLEX CATALYSTS
Dzhemilev, U. M.,Ibragimov, A. G.,Zolotarev, A. P.,Muslukhov, R. R.
, p. 297 - 299 (1992)
A new method is proposed for the synthesis of 2-vinylalkanes by the reactions of aluminocyclopentanes with allyl halides or ethers in presence of catalytic amounts of nickel or cobalt complexes. Keywords: synthesis, olefins, nickel complexes, cobalt complexes, catalysts, allyl compounds, phosphines, organoaluminum compounds, reduction, elimination.
Regio- and stereoselective synthesis for a novel class of organoaluminium compounds - substituted aluminacyclopentanes and aluminacyclopentenes assisted by zirconium catalysts
Dzhemilev, U.M.,Ibragimov, A.G.
, p. 1 - 4 (1994)
A novel regio- and stereoselective method has been developed for the catalytic cyclometallation of olefins and acetylenes with alkylalanes in the presence of Cp2ZrCl2, to give in one stage high yields of 3-substituted aluminacyclopentanes and aluminacyclopentenes.Applications of these reactions to a wide range of linear and cyclic olefins and to those containing functional substituents have been studied.The transformation of the aluminacyclopentanes thus produced, into five-membered heterocycles, mono- and di-substituted cyclobutanes and cyclopropanes, has been demonstrated.Key words: Alumina; Cyclopentane; Zirconium; Catalysis
Reactivity of mixed organozinc and mixed organocopper reagents: 14. Phosphine-nickel catalyzed aryl-allyl coupling of (n-butyl)(aryl)zincs. Ligand and substrate control on the group selectivity and regioselectivity
Kalkan, Melike,Erdik, Ender
, p. 28 - 36 (2016/06/09)
The group selectivity and regioselectivity in the allylation of mixed (n-butyl)(aryl)zinc reagents in THF depends on the nickel catalyst type and also on nature of the allylic substrate. Allylation of (n-butyl)(phenyl)zinc reagent with alkyl substituted primary allylic chlorides and acetates in the presence of NiCl2(dppf) catalysis affords the phenyl coupling product with γ-selectivity. However, allylation with aryl substituted primary allylic substrates results in both phenyl- and alkyl-coupling products with medium α-selectivity in the presence of NiCl2(dppf) catalysis whereas phenyl coupling product is formed with α-selectivity in the presence of NiCl2(Ph3P)2 catalysis. This new NiCl2(dppf) catalyzed protocol for γ-selective aryl allylation of (n-butyl)(aryl)zinc reagents with alkyl substituted primary allylic chlorides in THF at room temperature provides an atom economic alternative to allylation of (aryl)2Zn reagents. A mechanism for the dependence of group selectivity and regioselectivity of Ni catalyzed allylation of (n-butyl)(aryl)zinc reagents on the catalyst ligand and the substrate was proposed.
Reactivity of mixed organozinc and mixed organocopper reagents: 11. Nickel-catalyzed atom-economic aryl-allyl coupling of mixed (n-alkyl)(aryl)zincs
Kalkan, Melike
, p. 725 - 732 (2014/11/08)
Group selectivity in the allylation of mixed (n-butyl)(phenyl)zinc reagent can be controlled by changing reaction parameters. CuCN-catalyzed allylation in tetrahydrofuran (THF)-hexamethylphosphoric triamide is n-butyl selective and also γ-selective in the presence of MgCl2, whereas CuI-catalyzed allylation in THF in the presence of n-Bu3P takes place with a n-butyl transfer:phenyl transfer ratio of 23:77 and an α:γ transfer ratio of phenyl of 76:24. NiCl2(Ph3P) 2-catalyzed allylation in the presence of LiCl is phenyl selective with an α:γ ratio of 65:35. The reaction of methyl- or n-butyl(aryl)zinc reagents with an allylic electrophile in THF at room temperature in the presence of NiCl2(Ph3P)2 catalyst and LiCl as an additive provides an atom-economic alternative to aryl-allyl coupling using diarylzincs. Copyright
An insight into copper catalyzed allylation of alkyl zinc halides. Comparison of reactivity profiles for catalytic and stoichiometric alkylzinc-copper reagents
Erdik, Ender,Ko?o?lu, Melike
experimental part, p. 1890 - 1897 (2009/09/26)
The γ-selective allylation of catalytic and stoichiometric alkylzinc-cuprates have been kinetically studied. The reactivity profiles generated by allylation reactions of n-butylzinc chloride catalyzed by CuX compounds (X = I, Br, Cl, CN, SCN) and also cat
Copper catalyzed magnesium-Barbier reaction for γ-selective alkyl-allyl coupling
Erdik, Ender,Ko?o?lu, Melike
, p. 4211 - 4214 (2008/02/08)
CuCN catalyzed alkyl-allyl coupling under magnesium-Barbier conditions occurs regioselectively and affords predominantly the γ-products in good to high yields. This one-pot CuCN catalyzed reaction utilising Mg, an alkyl halide and an allylic substrate in THF at room temperature provides an easy alternative to the classical CuCN catalyzed γ-allylation of alkyl Grignard reagents.
'One-pot' synthesis of 1,1-disubstituted cyclopropanes in the presence of metal complex catalysts
Dzhemilev, Usein M.,Ibragimov, Askhat G.,Khafizova, Leyla O.,Ramazanov, Ilfir R.,Yalalova, Dina F.,Tolstikov, Genrikh A.
, p. 76 - 81 (2007/10/03)
A 'one-pot' catalytic method for the synthesis of 1,1-disubstituted cyclopropanes starting from olefins, acetylenes and AlEt3 in the presence of Cp2ZrCl2, via a step involving in situ formation of aluminacyclopentanes and aluminacyclopentenes, respectively, was developed. Five-membered organoaluminium compounds obtained without preliminary isolation are transformed to cyclopropanes under the effect of Ni(acac)2 in combination with allylhalogenides in the case of aluminacyclopentanes and alkylsulphates in experiments with aluminacyclopentenes.
Synthesis and transformation of metallacycles 25.* On a mechanism of the Ni(acac)2-catalyzed converson of 3-alkyl-1-ethylalumacyclopentanes into 1,1-disubstituted cyclopropanes
Dzhemilev,Ibragimov,Khafizova,Parfenova,Yalalova,Khalilov
, p. 1465 - 1468 (2007/10/03)
The reactions of 3-alkyl-1-ethylalumacyclopentanes with allyl halides in the presence of Ni(acac)2 as a catalyst were studied by dynamic NMR spectroscopy. Under the action of Ni complexes, alumacyclopentanes initially undergo intramolecular hydride transfer to give but-3-enyl(ethyl)aluminum hydrides and then react with the starting allyl halide, yielding but-3-enyl(ethyl)aluminum halides. Subsequent intramolecular carboalumination affords the corresponding 1,1-disubstituted cyclopropanes.
Cyclization of methyl-substituted 6-heptenyl radicals
Bailey, William F.,Longstaff, Sarah C.
, p. 2217 - 2219 (2007/10/03)
(Matrix presented) The behavior of a series of methyl-substituted 6-heptenyl radicals, generated from the corresponding iodides ((Me3Si)3SiH, AIBN in benzene at 80°C), has been investigated. The stereoselectivity of the 6-exo cyclizations, affording dimethylcyclohexanes, is low, and sizable quantities of methylcycloheptane, generated via 7-endo cyclization, are also produced.
Synthesis and transformations of metallocycles. 15. A novel method for β-vinylation of α-olefins with AlEt3 under the action of Ni- and Zr-containing catalysts
Ibragimov, A. G.,Zolotarev, A. P.,Muslukhov, R. R.,Lomakina, S. I.,Dzhemilev, U. M.
, p. 113 - 115 (2007/10/02)
A novel regioselective method has been developed for the synthesis of 2-substituted 1,3-butadienes by β-vinylation of α-olefins with AlEt3 in the presence of Ni- and Zr-containing catalysts. - Key words: dienes, synthesis; nickel complexes, catalysts; allyl compounds; organoaluminum compounds.
