17640-21-0Relevant articles and documents
Isopropyl 2-ethoxyacetate—an efficient acylating agent for lipase-catalyzed kinetic resolution of amines in batch and continuous-flow modes
Oláh, Márk,Boros, Zoltán,Hornyánszky, Gábor,Poppe, László
, p. 7249 - 7255 (2016/10/26)
Productivity [conversion (c) and specific reaction rate (rbatchor rflow)] and enantiomer selectivity [enantiomeric ratio (E) and enantiomeric excess (ee) of the products] of ethyl and isopropyl esters of acetic, 2-methoxyacetic and 2-ethoxyacetic acids as acylating agents were compared in the N-acylation of (±)-1-phenylethanamine rac-1 catalyzed by variously immobilized forms of Candida antarctica lipase B (CaLB) using shake flasks and continuous-flow reactors. The effect of the temperature in the 0–80 °C range on productivity and enantiomer selectivity in KRs of rac-1 was investigated with the isopropyl esters in continuous-flow mode using CaLB-filled minireactors. Isopropyl 2-ethoxyacetate surpassed the performance of ethyl 2-methoxyacetate in terms of both productivity (1.9–2.9 times higher rate in batch mode) and enantiomeric selectivity (ee(R)-amide>99.9% compared to 99.8%) providing at 40 °C high volumetric productivity (2.22 kg L?1h?1), specific reaction rate and enantiomeric excess (rflow=783 μmol min?1g?1, ee(R)-2c>99.9%).
Efficient and catalyst-free condensation of acid chlorides and alcohols using continuous flow
Van Waes, Frederik E. A.,Cukalovic, A.,Stevens, Christian V.,Drabowicz, J.
, p. 2776 - 2779,4 (2020/09/14)
An efficient, catalyst-free continuous flow procedure for the condensation of acid chlorides and alcohols was developed. Different esters could be obtained using this protocol with excellent conversions starting from the corresponding acid chlorides and alcohols in very short reaction times (5-7 min). The reaction was performed solventless for liquid reagents but requires a solvent for solid reagents in order to prevent clogging of the microreactor. Since no catalyst is needed, the purification of the reaction mixture is very straightforward. Scale-up of the reaction to a microreactor with an internal volume of 13.8 ml makes it possible to produce 2.2 g min-1 of ester with an isolated yield of 98% and recuperation of the formed HCl.
Method for the production of esters
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Page column 11-12, (2008/06/13)
The present invention relates to a novel process for the preparation of esters of the general formula I from compounds of the general formula II contained in aqueous solutions which comprises a) extracting the compounds of the general formula II directly or after liberation from their salts in the presence of a C1-C8-alcohol and a water-immiscible solvent and b) then esterifying with the C1-C8-alcohol in the presence of a catalyst and of an entraining agent under the conditions of an azeotropic distillation, where the process steps (a) and (b) can be carried out separately in terms of time and space or else in a successive continuous or batchwise sequence and where the variables and substituents in the formulae I and II have the following meanings: R1=F, Cl, —OH, —OC1-C10-alkyl, R2=H, C1-C10-alkyl; R3=C1-C8-alkyl, Q=—OH, —O?K+, where K+is an alkali metal cation or alkaline earth metal cation, n=0, 1 or 2.
