77-83-8Relevant articles and documents
Enantioselective epoxidation of β,β-disubstituted enamides with a manganese catalyst and aqueous hydrogen peroxide
Clarasó, Carlota,Vicens, Laia,Polo, Alfonso,Costas, Miquel
, p. 2430 - 2435 (2019/03/29)
Enantioselective epoxidation of β,β-disubstituted enamides with aqueous hydrogen peroxide and a novel manganese catalyst is described. Epoxidation is stereospecific and proceeds fast under mild conditions. Amides are disclosed as key functional groups to enable high enantioselectivity.
HClO4·SiO2-mediated improved isomerization of glycidic esters to α-hydroxy-β,γ -unsaturated esters: Application in the formal synthesis of (R)-Baclofen and β-phenyl GABA analogues
Basak, Ranjan,Dharuman, Suresh,Reddy, Y. Suman,Doddi, Venkata Ramana,Vankar, Yashwant D.
supporting information; experimental part, p. 325 - 327 (2012/06/01)
An efficient isomerization of glycidic esters to corresponding allylic alcohols, viz. α-hydroxy-β,γ -unsaturated esters has been brought about using HClO4·SiO2. Five of these allylic alcohols underwent selective SN2' nucleophilic substitution to generate γ-azido-α,β-unsaturated esters which were readily converted to an antispastic drug Baclofen and four other β-phenyl GABA analogues.
A versatile synthetic platform based on strained propargyl amines
He, Zhi,Yudin, Andrei K.
supporting information; experimental part, p. 1607 - 1610 (2010/06/16)
"Chemical Equation Presented" Divergent reactivity: Various ethynylaziridines behave as strained propargyl amines and can be directly converted into unprotected α-amino allenes by a highly diastereoselective SN2′ hydride delivery (see scheme). Additional reaction routes involve chemo- and regioselective transformation into either bicyclic aziridine/ enol ethers or highly strained azirine alkynes.
Malodour reducing composition and uses thereof
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, (2009/10/30)
The invention relates to a malodour reducing composition comprising: A) at least one phenylglycidate of formula (1): wherein: - R1 is a C1-C4 branched or linear alkyl group, - R2 is hydrogen or methyl, and - R3 is hydrogen, a C1-C4 branched or linear alkyl group or a methoxy group, and B) at least one 1,2 diketone of formula (2) or (3): wherein: - R4, R5 and R7 may be independently, a C1-C5 linear or branched alkyl or alkenyl group; - R6 is a (C1-C5) alkylidene; - R4 and R5 may also form a C4-C7 saturated or unsaturated alicyclic or heterocyclic ring structure, optionally substituted by (C1-C4) alkyl groups; - R6 and R7 may also form a C4-C7 unsaturated, alicyclic or heterocyclic ring structure optionally substituted by (C1-C4) alkyl groups; the weight ratio of glycidate A to 1,2 diketone B being from 1:99 to 99:1. The invention also relates to the fragrance compositions and consumer products containing this malodour reducing composition.
An efficient synthesis of 2-bromo-3-hydroxy esters by reaction of ketones with ethyl dibromoacetate promoted by samarium diiodide
Concellon, Jose M.,Concellon, Carmen,Diaz, Pamela
, p. 2197 - 2200 (2007/10/03)
A simple and efficient samarium diiodide mediated synthesis of 2-bromo-3-hydroxy esters 1 by the reaction of a variety of ketones 2 with ethyl dibromoacetate (3) is described. The relative configuration of the major diastereoisomer obtained was established by NOESY experiments of the corresponding α,β-epoxy esters 4 prepared from 1. Additionally, a mechanism is proposed to explain the results obtained. Wiley-VCH Verlag GmbH & Co. KGaA, 2006.
Organic reactions catalyzed by methylrhenium trioxide: Reactions of ethyl diazoacetate and organic azides
Zhu, Zuolin,Espenson, James H.
, p. 9901 - 9907 (2007/10/03)
Methylrhenium trioxide (CH3ReO3 or MTO) catalyzes several classes of reactions of ethyl diazoacetate, EDA. It is the first high valent oxo complex for carbene transfer. Under mild conditions and in the absence of other substrates, EDA was converted to a 9:1 mixture of diethyl maleate and diethyl fumarate. In the presence of alcohols, α-alkoxy ethyl acetates were obtained in good yield. The yields dropped for the larger and more branched alcohols, the balance of material being diethyl maleate and fumarate. An electron-donating group in the para position of phenols favors the formation of α-phenoxy ethyl acetates. The use of EDA to form α-thio ethyl acetates and N-substituted glycine ethyl esters, on the other hand, is hardly affected by the size or structure of the parent thiol or amine, with all of these reactions proceeding in high yield. MTO-catalyzed cycloaddition reactions occur between EDA and aromatic imines, olefins, and carbonyl compounds. Three-membered ring products are formed: aziridines, cyclopropanes, and epoxides, respectively. The reactions favor the formation of trans products, and provide a convenient route for the preparation of aziridines. Intermediate carbenoid and nitrenoid species have been proposed. In the presence of an oxygen source such as an epoxide, ethyl diazoacetate and azibenzil are converted to an oxalic acid monoethyl ester and tobenzil; at the same time the epoxide was converted to an olefin. These results provide further support for the proposed intermediate, a cyclic species containing Re, O, and CHCO2Et (or, occasionally, CPhC(O)Ph)in a three-membered ring.
REDUCTION OF ARYLALKYLAZOMETHINES WITH SODIUM BOROHYDRIDE
Dumpis, M. A.,Kudryashova, N. I.,Veresova, M. A.
, p. 1332 - 1337 (2007/10/02)
The secondary amines R1R2C6H3CH2CH(CH3)NHCHR5CHR6(CH2)nC6H3R3R4 were synthesized by the reduction of the respective azomethines with sodium borohydride.The reaction was conducted in anhydrous methanol in the presence of hydrogen chloride with the azomethine and hydrogen chloride in a molar ratio of 1:1.The yield was 50-90percent.The erythro and threo isomers were isolated, and the data from the IR spectra of the isomers are given.
α-Bromo-, α-chloro-, and α-trimethylsilyl-zinc ester enolates. New and universal Reformatsky-type Darzens and Peterson reactions
Fuerstner, Alois
, p. C33 - C36 (2007/10/02)
Low temperature reactions of ethyl dihaloacetates with carbonyl compounds in the presence of zinc/silver-graphite give α-halo-β-hydroxyalkanoates, which are readily converted into glycidates by base.Unser the same conditions ethyl(bromo)(trimethylsilyl) acetate with aldehydes and ketones forms α,β-unsaturated esters by a Reformatsky-Peterson reaction combination.
MASS SPECTROMETRIC DECOMPOSITION OF β-PHENYLOXIRANECARBOXYLIC ESTERS
Anisimova, O. S.,Chistyakov, V. V.,Bokanov, A. I.,Shvedov, V. I.,Sheinker, Yu. N.
, p. 1058 - 1063 (2007/10/02)
The electron-impact mass spectra of the E- and Z-isomers of the α,β-methyl substituted esters of β-phenyloxiranecarboxylic acids have been studied.
