55077-16-2Relevant academic research and scientific papers
Combination of Metal-Catalyzed Cycloisomerizations and Biocatalysis in Aqueous Media: Asymmetric Construction of Chiral Alcohols, Lactones, and γ-Hydroxy-Carbonyl Compounds
Rodríguez-álvarez, María J.,Ríos-Lombardía, Nicolás,Schumacher, S?ren,Pérez-Iglesias, David,Morís, Francisco,Cadierno, Victorio,García-álvarez, Joaquín,González-Sabín, Javier
, p. 7753 - 7759 (2017/11/10)
The combination of the metal-catalyzed cycloisomerization of alkynes containing a tethered nucleophile as substituent in aqueous media (followed by the spontaneous hydrolysis, hydroalkoxylation, or aminolysis of the transiently formed five-membered heterocycles) with the subsequent enantioselective ketone bioreduction (mediated by KREDs) has been achieved. The overall transformations, which formally involve a three-step one-pot reaction, provide a variety of enantiopure valuable molecules (e.g., 1,4-diols, lactones, and γ-hydroxy-carbonyl compounds (carboxylic acids, esters, and amides)) with high conversions and enantioselectivities and under mild reaction conditions, disclosing the concept of integrated metal-catalyzed cycloisomerizations of alkynes and enzymatic catalysis in water.
Base catalyzed sustainable synthesis of phenyl esters from carboxylic acids using diphenyl carbonate
Kreye, Oliver,Meier, Michael A. R.
, p. 53155 - 53160 (2015/06/25)
Phenyl esters were obtained in moderate to high yields by reaction of aliphatic and aromatic carboxylic acids with one equivalent of diphenyl carbonate in the presence of catalytic amounts of tertiary amine bases, such as DBU, TBD and DMAP under neat conditions at elevated temperatures (>100°C).
Reaction of dicarbonates with carboxylic acids catalyzed by weak Lewis acids: General method for the synthesis of anhydrides and esters
Bartoli, Giuseppe,Bosco, Marcella,Carlone, Armando,Dalpozzo, Renato,Marcantoni, Enrico,Melchiorre, Paolo,Sambri, Letizia
, p. 3489 - 3496 (2008/09/19)
The reaction between carboxylic acids (RCOOH) and dialkyl dicarbonates [(R1OCO)2O], in the presence of a weak Lewis acid such as magnesium chloride and the corresponding alcohol (R1OH) as the solvent, leads to the esters RCOOR1 in excellent yields. The mechanism involves a double addition of the acid to the dicarbonate, affording a carboxylic anhydride [(RCO)2O], R1OH and carbon dioxide. The esters arise from the attack of the alcohols on the anhydrides. Exploiting the lesser reactivity of tert-butyl alcohol in comparison with other alcohols, a clean synthesis of both carboxylic anhydrides and esters has been set up. In the former reaction, an acid/Boc2O molecular ratio of 2:1 leads to the anhydride in good to excellent yields, depending on the stability of the resulting anhydride to the usual workup conditions. In the latter reaction, stoichiometric mixtures of the acid and Boc2O are allowed to react with a twofold excess of a primary alcohol, secondary alcohol or phenol (R 2OH) to give the corresponding esters (RCOOR2). Purification of the products is particularly easy since all byproducts are volatile or water soluble. A very easy chromatography is required only in the case of nonvolatile alcohols. A broad variety of sensitive functional groups is tolerated on both the acid and the alcohol, in particular a high chemoselectivity is observed. In fact, no transesterification processes occur with the acid-sensitive acetoxy group and methyl esters. Georg Thieme Verlag Stuttgart.
Preparation of levulinic acid esters from alpha-angelica lactone and alcohols
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Page/Page column 5; 9, (2008/06/13)
The present invention relates to a process for producing levulinic acid esters from α-angelica lactone and alcohols in the presence of a basic catalyst. In addition, a method is described herein for producing fuel or fuel additives comprising levulinic acid esters produced from α-angelica lactone and alcohol. In addition, compositions are described comprising levulinic acid esters for use as fuel or fuel additives.
