4218-48-8Relevant academic research and scientific papers
Chemoselective Deoxygenation of 2° Benzylic Alcohols through a Sequence of Formylation and B(C6F5)3-Catalyzed Reduction
Oestreich, Martin,Richter, Sven C.
, p. 2103 - 2106 (2021/07/22)
A sequence of formylation and B(C6F5)3-catalyzed reduction of the resulting formate with Et3SiH enables the chemoselective deoxygenation of secondary benzylic alcohols. Primary benzylic and tertiary non-benzylic alcohols are not reduced by this protocol. The formyl group fulfills a double role as activator and self-sacrificing protecting group. The deoxygenation of these formates is fast and can be carried out in the presence of other potentially reducible groups. Neighboring-group participation was found in the deoxygenation of certain diol motifs.
Intermolecular Radical C(sp3)?H Amination under Iodine Catalysis
Bosnidou, Alexandra E.,Mu?iz, Kilian
, p. 7485 - 7489 (2019/04/30)
The direct amination of aliphatic C?H bonds has remained one of the most tantalizing transformations in organic chemistry. Herein, we report on a unique catalyst system, which enables the elusive intermolecular C(sp3)?H amination. This practical synthetic strategy provides access to aminated building blocks and fosters innovative multiple C?H amination within a new approach to aminated heterocycles. The synthetic utility is demonstrated by the synthesis of four relevant pharmaceuticals.
Hydrodeoxygenation Using Magnetic Induction: High-Temperature Heterogeneous Catalysis in Solution
Asensio, Juan M.,Miguel, Ana B.,Fazzini, Pier-Francesco,van Leeuwen, Piet W. N. M.,Chaudret, Bruno
supporting information, p. 11306 - 11310 (2019/07/12)
Magnetic heating has recently been demonstrated as an efficient way to perform catalytic reactions after deposition of the heating agent and the catalyst on a support. Here we show that in solution, and under mild conditions of mean temperature and pressure, it is possible to use magnetic heating to carry out transformations that are otherwise performed heterogeneously at high pressure and/or high temperature. As a proof of concept, we chose the hydrodeoxygenation of acetophenone derivatives and of biomass-derived molecules, namely furfural and hydroxymethylfurfural. These reactions are difficult, require heterogeneous catalysts and high pressures, and, to the best of our knowledge, have no precedent in standard solution. Here, hydrodeoxygenations are fully selective under mild conditions (3 bar H2, moderate mean temperature of the solvent). The reason for this reactivity is the fast heating of the particles well above the boiling temperature of the solvent and the local creation of hot spots surrounded by a vapor layer, in which high temperature and pressure may be present. This technology may be practicable for many organic transformations.
Isopropylation of ethyl benzene using MCM-41 and metals substituted MCM-41
Selvakumar,Stanly,Arabindoo, Banumathi
experimental part, p. 5313 - 5322 (2012/08/07)
Mesoporous MCM-41, Al-MCM-41, Fe-MCM-41, Mg-MCM-41 and Mn-MCM-41 were synthesized by hydrothermal process for catalytic applications. Tetradecyl trimethyl ammonium bromide was used as the structure directing template. Sodium silicate and salts of aluminium, iron, magnesium and manganese were the sources of silicon, aluminium, iron, magnesium and manganese, respectively. All the synthesised materials were characterised by BET, XRD and FTIR techniques. The XRD patterns of all the samples showed an intense signal at an angle of about 2?; (2θ) due to (100) plane of hexagonal mesophase. The patterns due to other planes were less intense. BET surface area of all the materials were in the range from 772-1273 m2/g and the pore diameter varies from 2.546- 2.663 nm. The catalytic performance of these materials has been tested for isopropylation of ethyl benzene. The influence of temperature, feed ratio and weight hourly space velocity (WHSV) were studied for all the aforesaid reactions for maximum conversion and product selectivity. In addition to p-isopropylethylbenzene, a commercially valuable compound diisopropyl ether was also obtained from isopropyl alcohol.
Catalytic process for selective alkylation of aromatic hydrocarbons
-
, (2008/06/13)
A catalytic process for the selective alkylation of mono- and polycyclic aromatic hydrocarbons is described. The aromatic hydrocarbon is reacted with an alkylating agent in the presence of an acid form of a dealuminated small pore mordenite catalyst having an atomic ratio Si/Al of at least 10:1 to thereby yield the desired alkyl substituted derivative with improved selectivity and improved yield.
PRODUCTS FROM SOLVOLYSIS OF 2-(2-TOSYLOXYETHYL)-6,6-DIMETHYLBICYCLOHEPT-2-ENE
Vyglazov, O. G.,Urbanovich, T. R.,Manukov, E. N.,Chuiko, V. A.,Udarov, B. G.
, p. 1896 - 1900 (2007/10/02)
The solvolysis of 2-(2-tosyloxyethyl)-6,6-dimethylbicyclohept-2-ene takes place with retention of the gem-dimethylcyclobutane ring of the substrate and is accompanied by simultaneous opening of the additional three-or four-membered ring in the reaction product.
Cyclodehydration of Non-aromatic Diols on Al(III)-Montmorillonite Clay: Reactivity and Mechanism
Kotkar, Dilip,Mahajan, Satish W.,Mandal, Arun K.,Ghosh, Pushpito K.
, p. 1749 - 1752 (2007/10/02)
Al(III)-Montmorillonite-catalysed reactions of non-aromatic diols and butane-1,4-dithiol into the corresponding heterocyclic compounds are described.Experiments with S-(+)-pentane-1,4-diol indicate a mechanism involving competitive protonation of the primary and secondary hydroxy groups, followed by SN2 displacement of water to form the cyclic product.A comparison of the relative catalytic efficiencies of Al(III)-montmorillonite and the corresponding alumina pillared clay suggests that the performance of the former is superior in the above acid-catalysed reactions.
Rearrangements of Pinane Derivatives. Part 91. 8,8-Dimethyltricyclo-2,5>nonan-2β-ol, a Tricyclic Pinane Derivative
Giddings, Rodney M.,Jones-Parry, Richard,Owen, Rawson,Whittaker, David
, p. 1525 - 1528 (2007/10/02)
Acetolysis of the toluene-p-sulphonate ester of 2-(2-hydroxyethyl)-6,6-dimethylbicyclohept-2-ene (nopol) (1; R = OH) gave a good yield of the acetate of the previously unknown tricyclic pinane derivative 8,8-dimethyltrycyclo2,5>n
RELATIONSHIP GOVERNING THE ALKYLATION OF AROMATIC HYDROCARBONS WITH ALLYL CHLORIDE AND BROMIDE IN THE PRESENCE OF SULFURIC ACID
Magerramov, M. N.
, p. 1485 - 1488 (2007/10/02)
The kinetic relationships governing the alkylation of aromatic hydrocarbons by allyl chloride and allyl bromide in the presence of sulfuric acid were studied.It was established that the reactivity of the aromatic hydrocarbons varies in relation to the "activity" of the allyl halides in the order allyl chloride > allyl bromide > propylene.
Alkyltrifluoromethanesulphonates as alkylating reagents for aromatic compounds
Booth, Brian L.,Haszeldine, Robert N.,Laali, Khosrow
, p. 2887 - 2893 (2007/10/02)
Methyl and ethyl trifluoromethanesulphonates (' triflates '), prepared by conventional routes involving either trifluoromethanesulphonic acid (' triflic acid ') or its anhydride, contain traces of triflic acid as an impurity, which catalyse their alkylation reactions with aromatic compounds. Pure methyl triflate, obtained from reaction between CH3l and CFS03Ag, does not alkylate p-cymene after several hours at 100 °C. Pure ethyl triflate, prepared by a similar method, is thermally less stable under these conditions, and alkylation takes place only after long induction periods during which some breakdown to triflic acid occurs. With aromatic substrates such as p-cymene or mesitylene the onset of alkylation is followed rapidly by the formation of isomerisation and disproportionation products. Benzyl triflate, prepared from PhCH2Br and CF3SO3Ag, alkylates p-cymene even at room temperature. The strong Lewis acids SbF5 and AlCl3 similarly catalyse alkylation reactions of methyl and ethyl triflates, but BF3, FeCl3, and SnCl4 are much less effective.
