2050-77-3Relevant articles and documents
The fluid-mosaic model, homeoviscous adaptation, and ionic liquids: Dramatic lowering of the melting point by side-chain unsaturation
Murray, Samuel M.,O'Brien, Richard A.,Mattson, Kaila M.,Ceccarelli, Christopher,Sykora, Richard E.,West, Kevin N.,Davis Jr., James H.
, p. 2755 - 2758 (2010)
(Figure Presented) Defying conventional wisdom: Ionic liquids (ILs) with long, unsaturated alkyl appendages (see top structure) defy established trends that link long ion-bound alkyl groups to higher melting points. The new ILs are also less viscous than a saturated standard (see bottom structure) at the same temperature. These features parallel those that underpin homeoviscous adaptation in certain organisms and are indirectly supportive of a fluid-mosaiclike nanoscale character.
Phase-Transfer Nucleophilic Reactions Using Water-Insoluble Alcohols as Organic Solvents
Ohtani, Noritaka,Inoue, Yukihiko,Shinoki, Noriyuki,Nakayama, Katsuhiro
, p. 2417 - 2424 (1995)
Simple nucleophilic substitutions were done under liquid-liquid phase-transfer reaction conditions using water-insoluble alcohols as organic solvents.The reactions proceeded at considerable rates even in the absence of any catalysts, depending on the alcohol, inorganic salt, and the aqueous concentration of the salts.An addition of single- or double-chained onium salts enhanced the reaction rate almost linearly with the amount of the onium salts.The concentrations of inorganic salts and water in the alcohol phase were analyzed and the relationship between these concentrations and the observed rate constant was discussed.An interfacial reaction mechanism explains the kinetics of this reaction system better than the conventional ion-pair mechanism assumed by most research using hydrocarbon solvents.
Catalytic Iodination of the Aliphatic C-F Bond by YbI3(THF)3: Mechanistic Insight and Synthetic Utility
Janjetovic, Mario,Ekebergh, Andreas,Tr?ff, Annika M.,Hilmersson, G?ran
supporting information, p. 2804 - 2807 (2016/07/06)
A facile iodination protocol of unactivated alkyl fluorides using catalytic amounts of YbI3(THF)3 in the presence of iodotrimethylsilane as a stoichiometric fluoride trapping agent is presented. 1H NMR spectroscopy demonstrates a two-step catalytic cycle where TMSI regenerates active YbI3(THF)3. Finally, the catalytic reaction is extended into a one-pot procedure to demonstrate a potential application of the method. Overall, the findings present a distinct strategy for C-F bond transformations in the presence of catalytic YbI3(THF)3.
A practical in situ generation of the schwartz reagent. reduction of tertiary amides to aldehydes and hydrozirconation
Zhao, Yigang,Snieckus, Victor
supporting information, p. 390 - 393 (2014/04/03)
A new, highly efficient in situ protocol (Cp2ZrCl2/LiAlH(OBu-t)3) is described for the generation of the Schwartz reagent which provides a convenient method for the amide to aldehyde reduction and the regioselective hydrozirconation-iodination of alkynes and alkenes. Highlighted are chemoselective reductions of benzamides derived by directed ortho metalation (DoM) chemistry, allowing the synthesis of valuable 1,2,3-substituted benzaldehydes. The single-step, three-component process proceeds in a very short reaction time, shows excellent functional group compatibility, and uses inexpensive and long-storage stable reducing reagents.
Asymmetric total synthesis of all four isomers of 6-acetoxy-5- hexadecanolide: The major component of mosquito oviposition attractant pheromones
Dong, Hong-Bo,Yang, Ming-Yan,Zhang, Xiao-Teng,Wang, Ming-An
, p. 610 - 616 (2014/05/20)
An asymmetric total synthesis of (5S,6R)-(+)-erythro-6-acetoxy-5- hexadecanolide 1a has been accomplished from readily available hex-5-yn-1-ol via Shi's asymmetric epoxidation as the key step, in eight steps with an overall yield of 33.5%. In addition, the stereoselective synthesis of all four isomers of 6-acetoxy-5-hexadecanolide 1a-1d were obtained via Sharpless asymmetric dihydroxylation and Mitsunobu reaction as the key steps with overall yields of 16.5-21.2%, respectively.
Selective C-F bond activation: Substitution of unactivated alkyl fluorides using YbI3
Traeff, Annika M.,Janjetovic, Mario,Ta, Linda,Hilmersson, Goeran
supporting information, p. 12073 - 12076 (2013/12/04)
F makes the break: The carbon-fluorine single bond is quite strong, thus making aliphatic C-F bond scission unusually challenging. A new methodology utilizing YbI3 leads to the conversion of a C-F bond into a C-I bond, and is compatible with various functional groups. The reaction is exceptionally selective towards alkyl fluorides and proceeds under mild conditions. Copyright
Ionic liquids as reagents and solvents in conjunction with microwave heating: Rapid synthesis of alkyl halides from alcohols and nitriles from aryl halides
Leadbeater, Nicholas E.,Torenius, Hanna M.,Tye, Heather
, p. 2253 - 2258 (2007/10/03)
We show that using ionic liquids as reagents in conjunction with microwave heating it is possible to prepare primary alkyl halides from the corresponding alcohols rapidly. Using ionic liquids as solvents in conjunction with microwave heating it is possible to prepare aryl nitriles from the corresponding aryl bromides or iodides. The scope and limitations of using microwave-promotion as a tool in these reactions is discussed.
A novel hydrogen transfer hydroalumination of alkenes with triisobutylaluminum catalyzed by Pd and other late transition metal complexes
Gagneur, Sebastien,Makabe, Hidefumi,Negishi, Ei-Ichi
, p. 785 - 787 (2007/10/03)
Hydrogen transfer hydroalumination of terminal alkenes and dienes can be achieved with 1.1 equiv. of (i-Bu)3Al and catalytic amounts of Cl2Pd(PPh3)2 and other late transition metal complexes containing Co, Rh, Ni, and Pt at ambient temperature in high yields.
Thiocyanation of alkyl halides with alkyl thiocyanates in the presence of quaternary phosphonium halides
Ohtani, Noritaka,Murakawa, Shigeki,Watanabe, Kohji,Tsuchimoto, Daisuke,Sato, Daiki
, p. 1851 - 1856 (2007/10/03)
Alkyl thiocyanates undergo simple SN2 reactions with the counter ions of quaternary phosphonium salts in nonpolar solvents and thiocyanate ions are liberated as the leaving ion. Depending on the nucleophile, the reaction proceeded irreversibly or reversibly. The reaction of benzyl thiocyanate with azide ions afforded a quantitative yield of benzyl azide. The reactions of alkyl thiocyanates with halide ions gave an equilibrium mixture where the reverse reaction of the alkyl halides produced with the liberated thiocyanate ions took place simultaneously. Thus, thiocyanate-halide exchange reactions between an alkyl thiocyanate and an alkyl halide were possible in the presence of a catalytic amount of a quaternary salt.
Hydrogen transfer hydrozirconation of alkenes with iBuZrCp2Cl catalyzed by Lewis-acidic metal compounds containing Al, Zn, Si, Ag, and Pd
Makabe, Hidefumi,Negishi, Ei-Ichi
, p. 969 - 971 (2007/10/03)
The hydrozirconation reaction of monosubstituted alkenes with iBuZrCp2Cl can be significantly accelerated by catalytic amounts of various Lewis acidic metal compounds, most notably AlCl3, Me3SiI, and Pd complexes, such as Li2PdCl4 and Cl2Pd(PPh3)2.
