16436-00-3Relevant articles and documents
Preparation, characterization and catalytic activity of MMT-clay exchanged sulphonic acid functionalized ionic liquid for transesterification of β-ketoesters
Ratti, Rajni,Kaur, Sukhbir,Vaultier, Michel,Singh, Vasundhara
, p. 503 - 507 (2010)
A novel solid acid catalyst 2 was prepared by ion exchange of sulphonic acid functionalized ionic liquid into clay interlayers as a new organic-inorganic hybrid catalytic system. The ionic tag of the imidazolium supported sulphonic acid 1 assists in the pillaring process and enhances the organophilicity of catalyst 2 in the interlayers of clay. The catalytic activity of catalyst 2 as a recyclable solid Bronsted acid has been tested for the chemoselective transesterification of ethyl/methyl β-ketoesters with various alcohols in good yields with high TON/TOF.
Transesterification of Methyl 2-Nitroacetate to Superior Esters
Corsi, Massimo,Machetti, Fabrizio,Magnolfi, Stefano
, (2020/03/19)
Methyl 2-nitroacetate and methyl acetoacetate have in common the presence of an electron-withdrawing substituent geminal to the methyl ester function but the well-known ease of thermal transesterification of methyl acetoacetate has not been found in methyl 2-nitroacetate. The latter gives uncatalysed thermal transesterification only in low yield and at a temperature higher than that of methyl acetoacetate. Comparative experiments provided further insight into the reactions; protic and Lewis acid catalysts promoted the smooth exchange of the alkanoyl groups, observing first the transesterification of methyl 2-nitroacetate with ethanol, already proved difficult to proceed. Dibutyltin(IV)oxide (DBTO) catalyst offered the spur to set up a convenient synthetic methodology from methyl 2-nitroacetate, encompassing higher molecular weight and functionalised alcohols: aliphatic, unsaturated and oxidation sensitive species were suited to react, delivering the corresponding 2-nitroacetate esters in good yields in most cases.
Synthesis of Fatty Acetoacetates Under Microwave Irradiation Catalysed by Sulfamic Acid in a Solvent-Free System
Weber, Andressa C. H.,Batista, Thaís C.,Gon?alves, Bruno,Hack, Carolina R. L.,Porciuncula, Larissa M.,Treptow, Tamara G. M.,D’Oca, Caroline Da R. Montes,Russowsky, Dennis,D’Oca, Marcelo G. Montes
, p. 1399 - 1406 (2016/09/28)
The 1,3-dicarbonyl compounds are important building blocks to obtain products with various biological activities and technological applications. In this work, we used a simple transesterification method to develop fatty acetoacetates in a solvent-free medium using a green catalyst, sulfamic acid (NH2SO3H), under microwave irradiation. The experimental results demonstrate good yields in a short reaction time (13?min), which makes this method an efficient approach to synthesize fatty acetoacetates from a wide range of saturated, unsaturated, and polyunsaturated long chain fatty alcohols, and ricinoleic derivatives. Experiments of recycling of the catalyst were performed and no decrease in catalytic activity of sulfamic acid was observed.
Nano CuFe2O4: An efficient, magnetically separable catalyst for transesterification of β-ketoesters
Gohain, Mukut,Kumar, Vinod,Van Tonder, Johannes H.,Swart, Hendrik C.,Ntwaeaborwa, Odireleng M.,Bezuidenhoudt, Barend C. B.
, p. 18972 - 18976 (2015/03/04)
The preparation of a variety of β-ketoesters was achieved in high yields from methyl acetoacetate under neutral conditions through the utilization of magnetic CuFe2O4 nanoparticles as catalyst. Recycling of the catalyst was performed up to eight times without significant loss in activity. The catalyst was characterized using XRD, XPS, SEM and TEM techniques.
