- Synthesis, Structure, Reactivity and Catalytic Implications of a Cationic, Acetylide-Bridged Trigold–JohnPhos Species
-
The cationic complex [(JohnPhos–Au)3(acetylide)][SbF6] (JohnPhos=(2-biphenyl)di-tert-butylphosphine, L1) has been characterised structurally and features an acetylide–trigold(I)–JohnPhos system; the trinuclear–acetylide unit, coordinated to the monodentate bulk phosphines, adopts an unprecedented μ,η1,η2,η1 coordination mode with an additional interaction between distal phenyl rings and gold centres. Other cationic σ,π-[(gold(I)L1)2] complexes have also been isolated. The reaction of trimethylsilylacetylene with various alcohols (iPrOH, nBuOH, n-HexOH) catalysed by cationic [AuIL1][SbF6] complexes in CH2Cl2 at 50 °C led to the formation of acetaldehyde acetals with a high degree of chemo- and regioselectivity. The reaction mechanism was studied, and several organic and inorganic intermediates have been characterised. A comparative study with the analogous cationic [CuIL1][PF6] complex revealed different behaviour; the copper metal is lost from the coordination sphere leading to the formation of cationic vinylphosphonium and copper nanoparticles. Additionally, a new catalytic approach for the formation of this high-value cationic vinylphosphonium has been established.
- Grirrane, Abdessamad,álvarez, Eleuterio,García, Hermenegildo,Corma, Avelino
-
p. 8810 - 8818
(2020/07/04)
-
- A catalytic conversion method for preparing pyruvate ester of lactic acid (by machine translation)
-
A method for preparing pyruvate through catalytic conversion of lactic acid is provided; according to the method, with oxygen or air as an oxidant, alcohol as a solvent, and molybdovanadophosphoric heteropoly acid and/or tungstovanadophosphoric heteropoly acid as a catalyst, and by coupling of a catalytic oxidation reaction and an esterification reaction, lactic acid is converted into pyruvate by one step. The method directly adopts oxygen or air as the oxidant and is green and safe; the used raw material lactic acid is obtained directly from conversion of biomass resources, moreover, the reaction conditions are mild, and the method has important application prospects.
- -
-
Paragraph 0019
(2016/10/10)
-
- Synthesis of Acetals Containing a Primary Amino Group
-
Amino acetals of the general formula MeCH(OR)(OXNH2) (R = Et, Bu, X = CH2CH2, CH2CH2CH 2, CH2CMe2) were synthesized in 53-91% yield by acid-catalyzed reaction of N-(2-hydroxyethyl)-, N-(3-hydroxypropyl)-, and N-(2-hydroxy-1,1-dimethylethyl)-2,2,2-trifluoroacetamides with vinyl ethers, followed by removal of the trifluoroacetyl protection by alkaline hydrolysis. Pleiades Publishing, Ltd., 2012.
- Lobanova,Stankevich,Kukharev
-
p. 1289 - 1296
(2013/02/21)
-
- Preparation of 1-phenylcyclohexa-2,5-diene-1-carboxylates and their use in free-radical mediated syntheses
-
Synthetic routes to pure 1-phenylcyclohexa-2,5-diene-1-carboxylic acid and derived esters were developed. Esters containing appropriately unsaturated side chains generated the corresponding alkenyl radicals and hence gave good yields of 5-exo ring closure products in organotin-free reactions. Extrusion of phenyl radicals from the intermediate cyclohexadienyl type radicals was not observed, and this alternative β-scission did not compete under any conditions. Yields from alkylations of olefins in analogous intermolecular processes were, however, poor. As a spin-off from the research, it was found that 1-phenylcyclohexa-2,5-diene-1-carboxylic acid (6) was a useful source of hydroxyformyl (formate) radicals in organic solvents.
- Baguley, Paul A.,Jackson, Leon V.,Walton, John C.
-
p. 304 - 309
(2007/10/03)
-
- Electrophilic Reactions of Activated Alkenes and Alkynes with Element Halides. III. Reaction of Activated Alkenes with Phosphorus Trihalides
-
Electrophilic substitution of the vinyl hydrogen atom in alkenyl alkyl ethers, 2-bromoethenyl alkyl ethers, and ketene acetals readily occurs under the action of phosphorus trihalides in the presence of an organic base to yield 70-98% of 2-alkoxy-, 2-alkoxy-1-bromo-, and 2,2-dialkoxyalkenylphosphonous dichlorides and dibromides. The reaction is regio- and stereospecific. A mechanism involving intermediate formation of a cyclic phosphiranium ion is proposed.
- Kazankova,Trostyanskaya,Efimova,Beletskaya
-
p. 1606 - 1619
(2007/10/03)
-
- Electrophilic Addition to Alkoxyethenes. XVI. Influence of Reagent Structure and Solvent on the Rate of Addition of Alcohols to Butyl Vinyl Ether
-
The influence of solvent and the structure of alcohol on the rate of its acid-catalyzed (HCl) addition to butyl vinyl ether was studied at 25 deg C in a mixture of the reacting alcohol with a solvent (1:4 by volume).The electrophilic attack of the substrate by solvated proton in the rate-determining stage is accompanied and facilitated by the simultaneous attack of the alkoxide ion on the resulting carboxonium center, i.e., the alcohol molecule participates in formation of the transition state.
- Nedolya, N. A.,Baranskii, V. A.,Trofimov, B. A.
-
p. 291 - 295
(2007/10/03)
-
- NEW THIOPROLINE DERIVATIVE
-
This invention relates to a new thioproline derivative represented by general formula (I), wherein X is one of dialkyl acetal, dialkyl thioacetal, cyclic acetal, cyclic dithioacetal, cyclic thioaminal and diacyloxymethyl groups; or one of hydroxyiminomethyl, lower alkylaminoiminomethyl, arylaminoiminomethyl and carbomoylaminoiminomethyl groups; or a 2-benzimidazolyl group. The invention also relates to an antiamnesiac drug and a proline endopeptidase inhibitor containing said derivative as the active ingredient.ψ
- -
-
-
- TELOMERISATION DES ETHERS VINYLIQUES ET LEUR COTELOMERISATION AVEC LES MONOMERES FLUORES
-
Radical cotelomerisation of vinylic ethers VE (butyl vinyl ether and 2-acetoxy ethyl vinyl ether) with chlorotrifluoroethylene and mercaptans (2-hydroxy ethyl mercaptane and C6F13C2H4SH) are studied.The homo-telomerization of vinylic ethers with these thiols and CCl3CH2OH leads to complex mixtures including acetals obtained by addition of the VE to hydroxy groups after telomerization of the thiol with the vinyl ether.Cotelomerization is similar, but we have also shown that the transfer activity of the thiols on all radical species bearing a vinyl ether end is very important and leads almost solely to monoadditions consuming large quantities of thiol.We deduce therefore, that in these reactions, we obtain mixtures of copolymers (formed after total consumption of the thiol) and of these adducts having a low molecular weight.
- Boutevin, B.,Cersosimo, F.,Youssef, B.
-
p. 403 - 418
(2007/10/02)
-
- REACTION OF THE OXIMES OF ALIPHATIC ALDEHYDES AND KETONES WITH ALKOXYETHENES
-
In the reaction of acetone oxime with alkyl vinyl ethers in the presence of zinc chloride variable amounts of acetone O,O'-(2-propylidene)dioxime, acetaldehyde dialkyl acetal, acetaldehyde O-(1-alkoxyethyl)oxide, and acetone O-(1-alkoxy-1-methylethyl)oxime, depending on the reaction conditions, are formed in addition to acetone O-(1-alkoxyethyl)oxime (the initial addition product).In the reaction of acetaldehyde oxime with alkyl vinyl ethers in the presence of zinc chloride acetaldehyde dialkyl acetal was isolated in addition to acetaldehyde O-(1-alkoxyethyl)oxime.A mechanism for the formation of the obtained compounds is proposed.
- Voronkov, M. G.,Keiko, N. A.,Shuvashev, Yu. A.,Kalikhman, I. D.,Keiko, V. V.
-
-
- REACTION OF 2-ETHOXYPROPIONAMIDE WITH ALKYL AND PHENYL VINYL ETHERS AND ALKYL α-FORMYLVINYL ETHERS
-
The addition of 2-ethoxypropionamide to alkyl and aryl vinyl ethers is accompanied by disproportionation of the initially formed adduct into symmetrical diamides and acetaldehyde acetal.In the reaction of the amide with phenyl vinyl ether the initial adduct N-(1-phenoxyethyl)-2-ethoxypropionamide was isolated.In contrast to the vinyl ethers, ethyl α-formylvinyl ether (2-ethoxyacrolein) reacts with 2-ethoxypropionamide not at the vinyl group but at the carbonyl group with the formation of N-(1-ethoxy-2-oxopropyl)-2-ethoxypropionamide and methylglyoxal diethyl acetal.
- Keiko, N. A.,Kuznetsova, T. A.,Kalikhman, I. D.,Chuvashov, Yu. A.,Voronkov, M. G.
-
p. 1464 - 1466
(2007/10/02)
-
- VINYL ETHERS CONTAINING AN EPOXY GROUP. FEATURES OF THE REACTION OF GLYCIDOL VINYLOXYETHYL ETHER WITH THIOLS
-
The reaction of thiols with glycidol vinyloxyethyl ether under radical and electrophilic conditions, leading to adducts at the vinyloxy group, was investigated.The reaction in the presence of perfluorobutyric and p-toluenesulfonic acids gives a mixture of "Markovnikov" and "anti-Markovnikov" addition products with a preference for the latter.Nine representations of the class of epoxy sulfides and their adducts with alcohol, thiols, amines, and urea were synthesized and characterized.It was found that the radical addition of the thiols to the vinyloxy group is accelerated in the presence of acids.This was explained by single-electron transfer between the thioanion and the carbenium ion.
- Nedolya, N. A.,Komel'kova, V. I.,Al'pert, M. L.,Trofimov, B. A.
-
p. 424 - 430
(2007/10/02)
-
- REACTION OF BUTOXYETHENE WITH OXIMES
-
The addition of the oximes of benzaldehyde, acetophenone, and acetone to butyl vinyl ether in the presence of acidic catalysts leads to the 0-(1-butoxyethyl)-oximes of the carbonyl compounds.Unlike aromatic oximes, acetone oxime forms a series of products with butyl vinyl ether.Among them a compound of a previously unknown series, i.e., acetone O,O'-(2-propylidene)dioxime was isolated.
- Voronkov, M. G.,Keiko,N. A.,Kalikhman, I. D.,Korostova, S. E.,Mikhaleva, A. I.,et al.
-
p. 695 - 696
(2007/10/02)
-
- REACTION OF THE AMIDES OF MONOCARBOXYLIC ACIDS WITH VINYL ALKYL ETHERS AND THE STRUCTURE OF THE ADDITION PRODUCTS
-
The reaction of vinyl alkyl ethers with the amides of monocarboxylic acids leads to the formation of 1,1-di(acylamino)ethanes.
- Voronkov, M. G.,Keiko, N. A.,Kuznetsova, T. A.,Frolov, Yu. L.,Kalikhman, I. D.,Chuvashev, Yu. A.
-
p. 1738 - 1741
(2007/10/02)
-