Enzymatic kinetic resolution of racemic cyanohydrins via enantioselective acylation

Xu, Qing; Xie, Yongli; Geng, Xiaohong; Chen, Peiran

doi:10.1016/j.tet.2009.11.074

Cited by 23 publications

(13 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Optically active cyanohydrins can be prepared either by asymmetric catalysis – mediated by metal–organic frameworks or metal complexes – or by biocatalytic methods based on the use of oxynitrilases or peptide‐based catalysts . Another relevant way to achieve the synthesis of optically active cyanohydrins uses lipase‐mediated kinetic resolution (EKR) reactions, which can be carried out through the acylation of cyanohydrins (Scheme , A) or by hydrolysis/alcoholysis of cyanohydrin esters (Scheme , B), in both cases with classical or dynamic resolution …”

Section: Introductionmentioning

confidence: 99%

“…Several examples of EKR reactions involving cyanohydrins have already been described. These involve acylation by Burkholderia cepacia and Candida antarctica lipase B; hydrolysis by Bacillus coagulans , Bacillus licheniformis , Candida rugosa , Pseudomonas aeruginosa , metagenome‐derived esterases, and several other proteases; alcoholysis by Candida antarctica lipase A, Candida antarctica lipase B, Candida rugosa , and Pseudomonas fluorescens ; and aminolysis by Candida antarctica lipase A . The published results indicate that, depending on the substrate structure, although good enantioselectivities can be achieved, long reaction times can be required to reach these high enantiomeric excesses.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

High‐Throughput Preparation of Optically Active Cyanohydrins Mediated by Lipases

et al. 2016

View full text Add to dashboard Cite

Cyanohydrins are versatile compounds with high applicability in organic synthesis; they are used as starting materials for the synthesis of other chemical targets with high industrial added value. Lipase‐mediated kinetic resolution reactions are a promising route for the synthesis of optically active cyanohydrins. These reactions can be carried out through the acylation of cyanohydrins or the deacylation of cyanohydrin esters, with different biocatalysts and under different reaction conditions. Unfortunately, depending on the substrate structure, long reaction times can be required to achieve suitable enantiomeric excesses. In this context, we present a high‐throughput protocol for the production of optically active cyanohydrins in continuous‐flow mode. The products were obtained with moderate to good enantioselectivity (E values from 8 up to >200) and with productivity values from 2.4 to 8.7 times higher in continuous‐flow mode than in batch mode. Moreover, the reaction times were reduced from hours in batch mode to minutes in continuous‐flow mode.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

High‐Throughput Preparation of Optically Active Cyanohydrins Mediated by Lipases

et al. 2016

View full text Add to dashboard Cite

show abstract

“…As also, the influence of substrate structure, steric and electronic nature and position of the aryl substituent on the enantioselectivity was discussed. 5 Optically active, mandelonitrile was obtained by the kinetic resolution (KR) in solvent-free system by lipase from Alcaligenes sp. and the reaction occurred within a short period of time at 5 h. This study showed that benzaldehyde and benzoic acid could inhibit the lipase activity.…”

Section: Introductionmentioning

confidence: 99%

Lipase-catalyzed kinetic resolution of (±)-mandelonitrile under conventional condition and microwave irradiation

Ribeiro¹,

Oliveira²,

Porto³

2012

J. Braz. Chem. Soc.

View full text Add to dashboard Cite

A resolução cinética da (±)-mandelonitrila foi realizada utilizando a lipase de Candida antarctica sob condição convencional (agitação orbital) e irradiação de micro-ondas em tolueno, produzindo o acetato de (S)-mandelonitrila com elevada seletividade (92-98% ee, excesso enantiomérico). O álcool remanescente da (R)-mandelonitrila sob irradiação de micro-ondas e agitação orbital foi parcialmente convertido em benzaldeído via equilíbrio químico espontâneo. O acetato de (S)-mandelonitrila foi produzido com 92% ee e rendimento de 35% em 8 h de reação sobre irradiação de micro-ondas. A transesterificação da (±)-mandelonitrila em agitador orbital produziu a (R)-mandelonitrila (51% ee) remanescente e o acetato da (S)-mandelonitrila (98% ee) de acordo com a regra Kazlauskas com 184 h de reação.The kinetic resolution of (±)-mandelonitrile was carried out using lipase from Candida antarctica under conventional condition (orbital shaker) and microwave irradiation in toluene, producing the (S)-mandelonitrile acetate with high selectivity (up to > 98% ee, enantiomeric excess). The unreacted (R)-mandelonitrile under microwave irradiation and conventional condition was partially converted into benzaldehyde by spontaneous chemical equilibrium. The (S)-mandelonitrile acetate under microwave irradiation was produced with 92% ee and 35% yield for 8 h of reaction. Conventional transesterification of (±)-mandelonitrile in an orbital shaker produced unreacted (R)-mandelonitrile (51% ee) and (S)-mandelonitrile acetate (98% ee) in accordance with Kazlauskas rule for 184 h of reaction.

show abstract

“…[10] 25 (R)-(-)-α-乙酰氧基-2-(4-甲氧基苯基)乙腈(3b): 无色液体 0.58 g, 产率 95%, GC 检测 99% ee, 柱温: 140 ℃, 载气: 1.0 mL/min, t major ＝50.7 min, t minor ＝56.1 min; 25 D [ ] α -7.0 (c 0.51, CHCl 3 ) [lit. [33] 26 (R)-(＋)-α-乙酰氧基-2-(3-甲氧基苯基)乙腈(3c): 无色液体 0.57 g, 产率 92%, GC 检测 99% ee, 柱温: 140 ℃, 载气: 1.0 mL/min, t major ＝40.8 min, t minor ＝43.4 min; 25 D [ ] α ＋5.0 (c 0.85, CHCl 3 ) [lit. [34] 20 [33] .…”

unclassified

“…[33] 26 (R)-(＋)-α-乙酰氧基-2-(3-甲氧基苯基)乙腈(3c): 无色液体 0.57 g, 产率 92%, GC 检测 99% ee, 柱温: 140 ℃, 载气: 1.0 mL/min, t major ＝40.8 min, t minor ＝43.4 min; 25 D [ ] α ＋5.0 (c 0.85, CHCl 3 ) [lit. [34] 20 [33] . [36] .…”

mentioning

confidence: 99%

Direct use of NaCN and aldehydes in one-pot asymmetric synthesis of cyanohydrins by crude (R)-oxynitrilase

Zheng¹,

Yao²,

Li³

et al. 2012

Chin. J. Org. Chem.

View full text Add to dashboard Cite

Solid sodium cyanide (NaCN) could be directly used to substitute volatile HCN as cyanide source in the one-pot asymmetric cyanohydrination of aldehydes catalyzed by crude (R)-oxynitrilase from almond with enough acetic acid to restrain the nonenzymatic reaction and racemization of chiral cyanohydrins. The effects of acid, crude (R)-oxynitrilase, volume ratio of water phase, NaCN and reaction temperature on the reaction were investigated. The yields and enantionmeric excess of most of products are higher than 95%. The proposed method has a high application value because of its simplicity, safety, and low cost as well as excellent enantioselectivities and yields.

show abstract

Enzymatic kinetic resolution of racemic cyanohydrins via enantioselective acylation

Cited by 23 publications

References 32 publications

High‐Throughput Preparation of Optically Active Cyanohydrins Mediated by Lipases

High‐Throughput Preparation of Optically Active Cyanohydrins Mediated by Lipases

Lipase-catalyzed kinetic resolution of (±)-mandelonitrile under conventional condition and microwave irradiation

Direct use of NaCN and aldehydes in one-pot asymmetric synthesis of cyanohydrins by crude (R)-oxynitrilase

Contact Info

Product

Resources

About