112-41-4Relevant articles and documents
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Mc Murry,Hoz
, p. 3797 (1975)
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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)
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.
Terminal olefins from aldehydes through enol triflate reduction
Pandey, Sushil K.,Greene, Andrew E.,Poisson, Jean-Francois
, p. 7769 - 7770 (2007)
(Chemical Equation Presented) The transformation of aldehydes into terminal olefins through reduction of the corresponding enol triflates is described. The method is effective with both linear and α-branched aldehydes.
AN IMPROVED METHOD FOR OLEFIN SYNTHESIS USING PYRIDYLSELENO GROUP AS A LEAVING GROUP
Toshimitsu, Akio,Owada, Hiroto,Uemura, Sakae,Okano, Masaya
, p. 5037 - 5038 (1980)
Alkyl pyridyl selenides are oxidized by 1.5 equiv. of 30percent H2O2 in THF to give olefins in good to excellent yields.The yields are always higher than the case where alkyl phenyl selenides are used under the same conditions.
Synthesis of amphiphilic thiatrimethinecyanines
Orlova,Kolchina,Shakirov,Gerasimova,Shelkovnikov
, p. 228 - 231 (2004)
Preparation conditions were optimized for 2-methyl-5-chlorobenzothiazolium quaternary salts with long-chain N-alkyl substituents (C12H 25, C15H31, C18H37). They were used in the synthesis of thiatrimethinecyanines conteining in the meso-position phenyl, p-chlorophenyl, or p-fluorophenyl groups.
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Robson,P. et al.
, p. 2180 - 2183 (1968)
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Ruthenium Chloride Catalysed Oxidation of Tertiary Amines to Amine Oxides with Molecular Oxygen
Riley, Dennis P.
, p. 1530 - 1532 (1983)
Tertiary amines are catalytically oxidized with molecular oxygen in homogeneous solutions containing RuCl3*xH2O to afford as a major product the corresponding N-oxide, the first example of such an oxidation.
Transition Metal-catalysed Elimination of Unactivated Sulfones
Gai, Yonghua,Jin, Liren,Julia, Marc,Verpeaux, Jean-Noel
, p. 1625 - 1626 (1993)
Lithiated tert-butyl alkyl sulfones undergo an easy elimination in the presence of catalytic amounts of bisacetylacetonatopalladium, thus leading to desulfonylated alkenes.
Catalytic deoxygenation of epoxides with (Cp*ReO)2(μ-O)2 and catalyst deactivation
Gable, Kevin P.,Zhuravlev, Fedor A.,Yokochi, Alexandre F.T.
, p. 799 - 800 (1998)
In situ reduction of Cp*ReO3 by PPh3 to form (Cp*ReO)2(μ-O)2 allows catalytic deoxygenation of epoxides, however, conproportionation between the ReV and ReVII species to form clusters of {(Cp*Re)3(μ-O)6}2+(ReO 4-)2 and new compound {(Cp*Re)3(μ2-O)3(μ 3-O)3ReO3}+(ReO4 -) leads to removal of rhenium from the catalytic cycle and loss of activity.
Contra-thermodynamic Olefin Isomerization by Chain-Walking Hydroboration and Dehydroboration
Bloomer, Brandon,Butcher, Trevor W.,Ciccia, Nicodemo R.,Conk, Richard J.,Hanna, Steven,Hartwig, John F.
, p. 1005 - 1010 (2022/02/10)
We report a dehydroboration process that can be coupled with chain-walking hydroboration to create a one-pot, contra-thermodynamic, short-or long-range isomerization of internal olefins to terminal olefins. This dehydroboration occurs by a sequence comprising activation with a nucleophile, iodination, and base-promoted elimination. The isomerization proceeds at room temperature without the need for a fluoride base, and the substrate scope of this isomerization is expanded over those of previous isomerizations we have reported with silanes.
Mild and efficient desulfurization of thiiranes with MoCl5/Zn system
Lee, Yeong Jin,Shin, Jeong Won,Yoo, Byung Woo
, (2021/11/10)
Desulfurization of a variety of thiiranes to alkenes occurs chemoselectively in high yields upon treatment with MoCl5/Zn system under mild conditions. The new methodology demonstrates high functional group tolerance toward chloro, bromo, fluoro, methoxy, ester, ether and keto groups.
Mild olefin formationviabio-inspired vitamin B12photocatalysis
Bam, Radha,Pollatos, Alexandros S.,Moser, Austin J.,West, Julian G.
, p. 1736 - 1744 (2021/02/22)
Dehydrohalogenation, or elimination of hydrogen-halide equivalents, remains one of the simplest methods for the installation of the biologically-important olefin functionality. However, this transformation often requires harsh, strongly-basic conditions, rare noble metals, or both, limiting its applicability in the synthesis of complex molecules. Nature has pursued a complementary approach in the novel vitamin B12-dependent photoreceptor CarH, where photolysis of a cobalt-carbon bond leads to selective olefin formation under mild, physiologically-relevant conditions. Herein we report a light-driven B12-based catalytic system that leverages this reactivity to convert alkyl electrophiles to olefins under incredibly mild conditions using only earth abundant elements. Further, this process exhibits a high level of regioselectivity, producing terminal olefins in moderate to excellent yield and exceptional selectivity. Finally, we are able to access a hitherto-unknown transformation, remote elimination, using two cobalt catalysts in tandem to produce subterminal olefins with excellent regioselectivity. Together, we show vitamin B12to be a powerful platform for developing mild olefin-forming reactions.