39520-22-4Relevant articles and documents
Preparation of mono-substituted malonic acid half oxyesters (SMAHOs)
Condon, Sylvie,Le Gall, Erwan,Pichon, Christophe,Presset, Marc,Xavier, Tania
supporting information, p. 2085 - 2094 (2021/09/02)
The use of mono-substituted malonic acid half oxyesters (SMAHOs) has been hampered by the sporadic references describing their preparation. An evaluation of different approaches has been achieved, allowing to define the best strategies to introduce diversity on both the malonic position and the ester function. A classical alkylation step of a malonate by an alkyl halide followed by a monosaponification gave access to reagents bearing different substituents at the malonic position, including functionalized derivatives. On the other hand, the development of a monoesterification step of a substituted malonic acid derivative proved to be the best entry for diversity at the ester function, rather than the use of an intermediate Meldrum acid. Both these transformations are characterized by their simplicity and efficiency, allowing a straightforward access to SMAHOs from cheap starting materials.
Exploiting the Continuous in situ Generation of Mesyl Azide for Use in a Telescoped Process
O'Mahony, Rosella M.,Lynch, Denis,Hayes, Hannah L. D.,Ní Thuama, Eilís,Donnellan, Philip,Jones, Roderick C.,Glennon, Brian,Collins, Stuart G.,Maguire, Anita R.
, p. 6533 - 6539 (2017/10/24)
The hazardous diazo transfer reagent mesyl azide has been safely generated and used in situ for continuous diazo transfer as part of an integrated synthetic process with an embedded safety quench. Diazo transfer to β-keto esters and a β-ketosulfone was successful. In-line phase separation, by means of a continuous liquid–liquid separator, enabled direct telescoping with a thermal Wolff rearrangement.
Synthesis of Enantiomerically Enriched 2-Hydroxymethylalkanoic Acids by Oxidative Desymmetrisation of Achiral 1,3-Diols Mediated by Acetobacter aceti
Brenna, Elisabetta,Cannavale, Flavia,Crotti, Michele,De Vitis, Valerio,Gatti, Francesco G.,Migliazza, Gaia,Molinari, Francesco,Parmeggiani, Fabio,Romano, Diego,Santangelo, Sara
, p. 3796 - 3803 (2016/12/24)
The stereoselective desymmetrisation of achiral 2-alkyl-1,3-diols is performed by oxidation of one of the two enantiotopic primary alcohol moieties by means of Acetobacter aceti MIM 2000/28 to afford the corresponding chiral 2-hydroxymethyl alkanoic acids (up to 94 % ee). The procedure, carried out in aqueous medium under mild conditions of pH, temperature and pressure, contributes to enlarge the portfolio of enzymatic oxidations available to organic chemists for the development of sustainable manufacturing processes.
Stereoselective synthesis of polyhydroxyl surfactants. Stereochemical influence on Langmuir monolayers
Neimert-Andersson, Kristina,Blomberg, Eva,Somfai, Peter
, p. 3746 - 3752 (2007/10/03)
Herein is described the synthesis of surfactants featuring polyhydroxylated head groups. Three head groups were prepared via consecutive stereoselective dihydroxylations of a diene. By coupling of these with lipophilic tail groups six novel surfactants have been prepared. The monolayers prepared from four of these have been investigated at the air-water interface. Significant differences were observed between monolayers consisting of enantiomerically pure surfactants contra racemates as well as between diastereomers.
Electrooxidation of malonate and acetylacetate derivatives in the presence of halide ions
Okimoto, Mitsuhiro,Takahashi, Yukio
, p. 2215 - 2219 (2007/10/03)
β-Dicarbonyl compounds, such as dimethyl malonate derivatives and methyl acetoacetate derivatives, were electrooxidized in methanol in the presence of halogen ions to afford the corresponding dimethyl α-halomalonates and methyl α-halocarboxylates. Electrooxidation of bis(β-dimethoxycarbonyl) derivatives similarly afforded cyclic compounds and dihalides.
Preparation of phosphinodipeptide analogs as building blocks for pseudopeptides synthesis
Cristau, Henri-Jean,Coulombeau, Agnès,Genevois-Borella, Arielle,Sanchez, Frédéric,Pirat, Jean-Luc
, p. 381 - 391 (2007/10/03)
A simple and effective preparation of phosphinodipeptides, in good overall yields, has been developed. This one pot procedure, allowing the variation of the substituents in α and/or β position to the phosphorus atom and also in α position to the nitrogen atom, consists in the addition of alkyl hypophosphites to imines, followed by Michael-addition on acrylates. To show the value of phosphinodipeptides analogs 1 as synthetic intermediates, selective deprotections of the three functional groups are described.
Electrochemically induced oxidative rearrangement of alkylidenemalonates
Elinson, Michail N.,Feducovich, Sergey K.,Nikishin, Gennady I.
, p. 14529 - 14540 (2007/10/03)
Alkylidenemalonates capable of double bond migration being electrolyzed in methanol or ethanol in the presence of alkali metal halides in an undivided cell equipped with Fe cathode are transformed into 2-alkyl-3,3- dimethoxyalkane-1,2-dicarboxylates in 70-90% yield via electrochemically induced oxidative rearrangement. Acidification of the reaction mixture after the electrolysis leads to the formation of 2-alkyl-3-oxoalkane-1,1- dicarboxylates. In the case of isobutylidenemalonate, the electrolysis intermediate dimethyl 3,3-dimethyl-2-methoxy-cyclopropane-1,1-dicarboxylate was isolated in 70% yield.
Electrochemical Cyclodimerization of Alkylidenemalonates
Elinson, Michail N.,Feducovich, Sergey K.,Zakharenkov, Alexandre A.,Ugrak, Bogdan I.,Nikishin, Gennady I.,et al.
, p. 5035 - 5046 (2007/10/02)
Electrolysis of dimethyl alkylidenemalonates RCH=C(COOMe)2 (R=n-Alk, Ph) in an undivided cell in MeOH in the presence of alkali metal halide as mediator, leads to the formation of cyclic dimers, i.e., 3,4-disubstituted 1,1,2,2-cyclobutanetetracarboxylates.The reaction proceeds via the reductive coupling of two substrate molecules at cathode and the cyclization of a hydrodimer dianion by its interaction with an active form of a mediator, an anode-generated halogen.
Electrochemical cyclodimerization of alkylidenemalonates into 3,4-disubstituted cyclobutane-1,1,2,2-tetracarboxylates
Nikishin, Gennady I.,Elinson, Michail N.,Feducovich, Sergey K.,Ugrak, Bogdan I.,Struchkov, Yuri T.,Lindeman, Sergey V.
, p. 3223 - 3226 (2007/10/02)
Alkylidenemalonates being electrolyzed in methanol in undivided cell with glassy carbon, carbon or lead cathode in the presence of sodium iodide or sodium bromide are transformed into 3,4-disubstituted cyclobutane-1,1,2,2-tetracarboxylates.