126641-87-0

Upstream product

• 108-05-4 vinyl acetate 
• 39515-47-4 2-hydroxy-2-(3-phenoxyphenyl)acetonitrile 
• 108-22-5 Isopropenyl acetate 
• 61066-87-3 alpha-cyano-3-phenoxybenzyl acetate 
• 39515-51-0 3-Phenoxybenzaldehyde 
• 75-86-5 2-hydroxy-2-methylpropanenitrile 
• 108-24-7 acetic anhydride 
• 151-50-8 potassium cyanide 
• 110-87-2 3,4-dihydro-2H-pyran 
• 123-20-6 vinyl n-butyrate 
• 69739-34-0 t-butyldimethylsiyl triflate 
• 3282-30-2 pivaloyl chloride 
• 631-57-2 Acetyl cyanide 
• 82129-02-0 2-(3-phenoxyphenyl)-2-[(trimethylsilyl)oxy]acetonitrile 

Relevant academic research and scientific papers

Chemo-enzymatic synthesis of (S)-α-cyano-3-phenoxybenzyl alcohol

A chemo-enzymatic process for the preparation of (S)-α-cyano-3- phenoxybenzyl alcohol (S-CPBA), an important intermediate in the synthesis of many pyrethroids, was developed. The process consists of four stages, including lipase-mediated resolution. The first stage, the synthesis of racemic α-cyano-3-phenoxybenzyl acetate (CPBAc) from m-phenoxybenzaldehyde (m-PBA) and sodium cyanide in the presence of a phase transfer catalyst, resulted in a 75% yield with 95% purity. The second key step is the resolution of the racemic ester by a highly enantioselective lipase from Pseudomonas sp. The immobilized enzyme carried out the transesterification reaction to nearly full conversion (46% out of 50%) with an enantiomeric excess of >96%. The enzymatic reaction was accomplished in a batch system as well as in a fluidized bed column. The reaction was found to be inhibited by accumulation of the product and to a lesser extent, by the aldehyde. The separation of the enantiomerically pure alcohol from the undesired ester was performed by chromatographic techniques, as well as by extraction with hexane. The final racemization step of the (R)-ester was easily attained with the use of triethylamine in diisopropyl ether or toluene. The process was shown to be feasible on a gram scale and shows potential for scale up.

Synthesis of (1R,cis,αS)-cypermethrine via lipase catalyzed kinetic resolution of racemic m-phenoxybenzaldehyde cyanohydrin acetate

A technical scale preparation of optically active (1R,cis, αS)- cypermethrine 4 from racemic m-phenoxybenzaldehyde cyanohydrin acetate (RS)- 1 and (1R,cis)-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropane-carboxylic acid chloride (1R,cis)-3 is described. Key steps of the new procedure are a lipase catalyzed enantioselective transesterification of (RS)-1 with n-butanol and direct acylation of the mixture of (R)-1 and (S)-cyanohydrin (S)-2 with (1R,cis)-3 to give enantiomerically pure (1R,cis,αS)-4. The unchanged (R)-1 is removed from (1R,cis,αS)-4 by distillation, and is racemized with triethylamine to give (RS)-1 which is returned to the process. The total yield of (1R,cis,αS)-4 referred to (RS)-1 is 80%.

A High-Throughput Screening Method for the Directed Evolution of Hydroxynitrile Lyase towards Cyanohydrin Synthesis

Chiral cyanohydrins are useful intermediates in the pharmaceutical and agricultural industries. In nature, hydroxynitrile lyases (HNLs) are a kind of elegant tool for enantioselective hydrocyanation of carbonyl compounds. However, currently available methods for demonstrating hydrocyanation are still stalled at precise, but low-throughput, GC or HPLC analyses. Herein, we report a chromogenic high-throughput screening (HTS) method that is feasible for the cyanohydrin synthesis reaction. This method was highly anti-interference and sensitive, and could be used to directly profile the substrate scope of HNLs either in cell-free extract or fermentation clear broth. This HTS method was also validated by generating new variants of PcHNL5 that presented higher catalytic efficiency and stronger acidic tolerance in variant libraries.

Fast microwave-assisted resolution of (±)-cyanohydrins promoted by lipase from Candida antarctica

Enzymatic kinetic resolution (EKR) of (±)-cyanohydrins was performed by using immobilized lipase from Candida antarctica (CALB) under conventional ordinary conditions (orbital shaking) and under microwave radiation (MW). The use of microwave radiation contributed very expressively on the reduction of the reaction time from 24 to 2 h. Most importantly, high selectivity (up to 92percent eep) as well as conversion was achieved under MW radiation (50-56percent).

Lewis acid-lewis base-catalysed enantioselective addition of α-ketonitriles to aldehydes

Additions of structurally diverse α-ketonitriles to aromatic and aliphatic prochiral aldehydes yielding highly enantioenriched acylated cyanohydrins were achieved using a combination of a titanium salen dimer and an achiral or chiral Lewis base. In most cases high yields and high enantioselectivities were observed. The ee was moderate in the initial part of the reaction but increased over time. This could be avoided, and higher ees obtained, by keeping the titanium complex, in the presence or absence of aldehyde and ketonitrile, at -40°C prior to the addition of the Lewis base. A mechanism initiated by nucleophilic attack of the tertiary amine at the carbonyl carbon atom of the ketonitile is supported by 13C labelling experiments.

Asymmetric cyanosilylation of aldehydes catalyzed by novel organocatalysts

A novel proline-based N,N′-dioxide, which is easily prepared from inexpensive chemicals, serves as an effective catalyst for enantioselective cyanosilylation of aldehydes in up to 73% ee. Georg Thieme Verlag Stuttgart.

Enantioselective addition of trimethylsilyl cyanide to aldehydes catalysed by bifunctional BINOLAM-AlCl versus monofunctional BINOL-AlCl complexes

A highly enantioselective cyanation of aldehydes takes place by using a bifunctional catalyst derived from 3,3′-bis(diethylaminomethyl) substituted binaphthol (BINOLAM) and dimethylaluminium chloride. The addition is of wide scope and runs best in toluene at temperatures ranging from -20 to -40°C, in the presence of 4 A? MS and triphenylphosphine oxide as additives. The (R)- or (S)-cyanohydrins result when using (S)- or (R)-BINOLAM-AlCl complexes, respectively. The valuable ligand can be recovered by simple extractive work-up and recycled without loss of efficiency (both in terms of chemical and stereochemical yields). This methodology is applied to the Shibasaki synthesis of epothilone A. All the evidence available for the BINOLAM-AlCl enantioselective addition of TMSCN to aldehydes call for the intervention of a hydrocyanation reaction, addition of a catalytic amount of hydrogen cyanide, generated in situ, to an aldehyde, followed by O-silylation. In order to determine the role of the basic amino groups of BINOLAM, comparative studies are carried out with the monofunctional 1,1′-binaphthol-derived complex BINOL-AlCl. Graphical Abstract.

Polymeric salen-Ti(IV) or V(V) complex catalyzed asymmetric synthesis of O-acetylcyanohydrins from KCN, Ac2O and aldehydes

Polymeric salen-Ti(IV) and V(V) complexes were employed in the enantioselective O-acetyl cyanation of aldehydes with potassium cyanide and acetic anhydride. The crosslinked polymeric salen-Ti(IV) catalyst exhibited good activities and enantioselectivities, up to 91% ee with 99% conversion was obtained at -20°C with 1 mol% of catalyst (based on bimetallic catalytic unit). Moreover, six consecutive recyclings with the easily recovered crosslinked polymeric catalyst showed no obvious decrease in either activity or enantioselectivity. Linear polymeric salen-V(V) catalyst showed good catalytic efficiency too, up to 94% ee with 99% conversion was obtained at -42°C with 5 mol% of catalyst. Graphical Abstract.

Asymmetric addition of KCN and Ac2O to aldehydes catalyzed by recyclable polymeric salen-Ti(IV) complexes

Polymeric salen-Ti(IV) complexes were employed in the enantioselective O-acetyl cyanation of aldehydes with KCN and Ac2O. The polymeric catalysts with appropriate crosslinking degree exhibited good activities and enantioselectivities, up to 94%

Process for the cyanation of aldehydes

A process for cyanating an aldehyde is provided. The process comprises reacting the aldehyde with: i) a cyanide source which does not comprise a Si—CN bond or a C—(C=O)—CN moiety; and ii) a substrate susceptible to nucleophilic attack not comprising a hal