1632-16-2Relevant articles and documents
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 (2001)
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.
'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 (2001)
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.
Elongation and branching of a-olefins by two ethylene molecules
Dietel, Thomas,Lukas, Fabian,Kretschmer, Winfried P.,Kempe, Rhett
, p. 1021 - 1024 (2022/03/15)
a-Olefins are important starting materials for the production of plastics, pharmaceuticals, and fine and bulk chemicals. However, the selective synthesis of a-olefins from ethylene, a highly abundant and inexpensive feedstock, is restricted, and thus a broadly applicable selective a-olefin synthesis using ethylene is highly desirable. Here, we report the catalytic reaction of an a-olefin with two ethylene molecules. The first ethylene molecule forms a 4-ethyl branch and the second a new terminal carbon-carbon double bond (C2 elongation). The key to this reaction is the development of a highly active and stable molecular titanium catalyst that undergoes extremely fast b-hydride elimination and transfer.
Renewable plasticizer alcohols from olefin oligomers and methods for making the same
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Page/Page column 5, (2018/04/20)
An efficient, low-temperature process to convert well-defined olefin oligomers, particularly butene oligomers to branched chain alcohols suitable for use as precursors to plasticizers commonly used in industry, and more specifically, the olefin feedstocks can be conveniently and renewably produced from short chain alcohols.
Thermally induced structural transformations of linear coordination polymers based on aluminum tris(diorganophosphates)
D?bowski, Maciej,?okaj, Krzysztof,Ostrowski, Andrzej,Zachara, Janusz,Wiecińska, Paulina,Falkowski, Pawe?,Krztoń-Maziopa, Anna,Florjańczyk, Zbigniew
supporting information, p. 16480 - 16491 (2018/12/05)
The thermal transitions of inorganic-organic hybrid polymers composed of linear aluminum tris(diorganophosphate) chains with a general formula of catena-Al[O2P(OR)2]3 (where R = C1-C8 alkyl group or phenyl moiety) have been studied by means of DSC, powder XRD, TGA and TG-QMS, as well as optical spectroscopy. DSC and XRD reveal that most of them undergo reversible structural transformations in the solid state between ?100 and 200 °C caused by the changes in conformation of their organic substituents; however, a translational displacement of the rigid polymeric chains occurs only in the case of the derivative bearing long 2-ethylhexyl groups, which becomes liquid at about 140 °C. The thermal decomposition of the studied polymers begins between 200 and 265 °C depending on the type of organic substituent R decorating their aluminophospate core. TGA combined with mass spectrometry of the evolved gaseous products shows that the pyrolytic decomposition of Al[O2P(OR)2]3 proceeds either through β-elimination of olefin (for compounds with C2-C8 aliphatic ligands), or a homolytic cleavage of the P-OR bond (for methyl and phenyl derivatives); both processes are accompanied by condensation of the newly formed POH groups and liberation of water. Powder XRD, FTIR and SEM analyses of the solid residues indicate that thermolysis of Al[O2P(OR)2]3 accompanied by olefin elimination leads to the formation of condensed aluminum phosphates, mainly aluminum cyclohexaphosphate, exhibiting porous morphology. On the other hand, thermal degradation of methyl or phenyl derivatives results in amorphous aluminophosphate residues, and the latter contains conducting carbonaceous phases.
Effect of Alcohol Structure on the Kinetics of Etherification and Dehydration over Tungstated Zirconia
Rorrer, Julie,Pindi, Suresh,Toste, F. Dean,Bell, Alexis T.
, p. 3104 - 3111 (2018/09/06)
Linear and branched ether molecules have attracted recent interest as diesel additives and lubricants that can be produced from biomass-derived alcohols. In this study, tungstated zirconia was identified as a selective and green solid acid catalyst for the direct etherification of primary alcohols in the liquid phase, achieving ether selectivities of >94 % for C6–C12 linear alcohol coupling at 393 K. The length of linear primary alcohols (C6–C12) was shown to have a negligible effect on apparent activation energies for etherification and dehydration, demonstrating the possibility to produce both symmetrical and asymmetrical linear ethers. Reactions over a series of C6 alcohols with varying methyl branch positions indicated that substituted alcohols (2°, 3°) and alcohols with branches on the β-carbon readily undergo dehydration, but alcohols with branches at least three carbons away from the -OH group are highly selective to ether. A novel model compound, 4-hexyl-1dodecanol, was synthesized and tested to further demonstrate this structure–activity relationship. Trends in the effects of alcohol structure on selectivity were consistent with previously proposed mechanisms for etherification and dehydration, and help to define possible pathways to selectively form ethers from biomass-derived alcohols.
DIARYL AMINE ANTIOXIDANTS PREPARED FROM BRANCHED OLEFINS
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Paragraph 0058; 0059, (2017/02/09)
Diaryl amines are selectively alkylated by reaction with branched olefins, which olefins are capable of forming tertiary carbonium ions and can be conveniently prepared from readily available branched alcohols. The diaryl amine products are effective antioxidants and often comprise a high amount of di-alkylated diaryl amines and a low amount of tri- and tetra-alkylated diaryl amines.
Oligomerization of 1-butene with a homogeneous catalyst system based on allylic nickel complexes
Behr,Bayrak,Peitz,Stochniol,Maschmeyer
, p. 41372 - 41376 (2015/05/27)
The oligomerization of 1-butene with a nickel-based catalyst system constitutes an elegant synthesis method for obtaining linear octenes from readily available chemicals. It is well known that the bis-(cyclooctadiene)nickel(0)-complex (Ni(COD)2) can be used in combination with 1,1,1,5,5,5-hexafluoroacetylacetone (hfacac) forming [Ni-1] as a catalyst for the dimerization of 1-butene, which produces a linear octene yield of 75-83% at reaction temperatures between 70-80 °C. We are the first to demonstrate that it is also possible to use allylic nickel complexes in combination with hfacac to produce linear octenes with a selectivity of 70% under very mild reaction conditions and at low catalyst concentrations. Additionally the catalyst can be formed simply by adding the activator hfacac to a solution of the allylic nickel complex. No complicated synthesis or purification is needed.
Isononylamines from 2-Ethylhexanol, Processes for Their Preparation, and Their Use
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Paragraph 0056-0057, (2015/06/10)
Process for preparing isononylamines starting out from 2-ethylhexanol, characterized in that (a) 2-ethylhexanol is dehydrated in the presence of a catalyst to form octene; (b) the octene obtained in step a) is reacted with carbon monoxide and hydrogen in the presence of a transition metal compound of group VIII of the Periodic Table of the Elements to form isononanal; and (c) the isononanal obtained in step b) is converted into isononylamines.
Vinyl Esters of Isononanoic Acid Starting from 2-Ethyl Hexanol, Methods for the Production Thereof and Use Thereof
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Paragraph 0075-0077, (2015/06/24)
Process for preparing the vinyl ester of isononanoic acid starting out from 2-ethylhexanol, characterized in that (a) 2-ethylhexanol is dehydrated in the presence of a catalyst to form octene; (b) the octene obtained in step a) is converted into an isononanoic acid having one more carbon atom; and (c) the isononanoic acid obtained in step b) is converted into the corresponding vinyl ester.
