84569-91-5

Upstream product

• 630-19-3 pivalaldehyde 
• 75-86-5 2-hydroxy-2-methylpropanenitrile 
• 7677-24-9 trimethylsilyl cyanide 
• 74-90-8 hydrogen cyanide 
• 134863-87-9 (R)-2-trimethylsilanyloxy-3,3-dimethylbutanonitrile 
• 151-50-8 potassium cyanide 

Downstream Products

• 70489-63-3 (R)-2-hydroxy-3,3-dimethyl-1-aminobutane 

Relevant academic research and scientific papers

Preparation of Chiral Cyanohydrins by an Oxynitrilase-Mediated Transcyanation

The transcyanation of aromatic and aliphatic aldehydes 1 (RCHO) with acetone cyanohydrin is catalyzed by the enzyme D-oxynitrilase to afford (R)-cyanohydrins 2 (RCH(OH)CN).The biocatalytic method using acetone cyanohydrin gives products of high enantiomeric purity with better consistency than similar conditions using hydrogen cyanide as the cyanide source.The use of an ether-buffer biphasic solvent system is essential for producing products of optimum optical purity, but the solubility properties of the substrate have a pronounced effect on the enantiomeric purity of the final product.A discussion relating the solubility partition coefficient (log P) of a substrate to the enantiomeric purity of the product as a guide for predicting the outcome with new substrates is presented.Application of the method to the preparation of the following cyanohydrins is reported (R, ee): a, C6H5, 92percent ee; b, 3,4-(CH2O2)C6H3, 90percent ee; c, 2-(CH3O)C6H4, 96percent ee; d, C6H5CH2, 88percent ee; e, CH3SCH2CH2, 92percent ee; f, CH3(CH2)5CH2, 92percent ee; g, (CH3)3C, 92percent ee; h, c-C6H11, 96percent ee; i, CH3O2C(CH2)6CH2, 97percent ee; j, (E,E)-CH3CH=CHCH=CH, 96percent ee; k, (CH3)2C=CHCH2CH2C(CH3)=CH, 99percent ee.

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.

R-HNL random variants and their use for preparing optically pure, sterically hindered cyanohydrins

The invention relates to R -hydroxynitrile lyases with improved substrate acceptance, increased activity and increased selectivity, obtainable by introducing random mutations with the aid of random mutagenesis and/or saturation mutagenesis techniques, ide

Enantioselective silylcyanation of aldehydes catalyzed by new chiral oxovanadium complex

Oxovanadium(V) complex 4 was prepared from VOSO4 and tridentate Schiff base ligand, which was prepared from substituted salicylaldehyde and inexpensive (S)-valine. Asymmetric silylcyanation of the aldehydes catalyzed by catalyst 4 afforded cyanohydrins with good enantioselectivities.

Enantioselective hydrocyanation of aldehydes catalyzed by [Li{Ru(phgly)2(binap)}]X (X = Cl, Br)

Novel bimetallic complexes [Li{Ru[(S)-phgly]2[(S)-binap]}]X (X = Cl, Br) are readily synthesized by mixing Ru[(S)-phgly]2[(S)-binap] and LiX. A single-crystal X-ray analysis reveals the structure. These bimetallic complexes efficient

Room-temperature synthesis of enantioenriched non-protected cyanohydrins using vanadium(salalen) catalyst

Room-temperature synthesis of enantioenriched non-protected cyanohydrins using acetone cyanohydrin as the cyanide source was achieved by V(salalen) catalyst. Aliphatic aldehydes underwent the cyanation with 89-95% ee in the presence of only 0.2-0.4 mol% catalyst. Aromatic cyanohydrins were also obtained in high enantiomeric excesses under modified conditions.

Vanadium-catalyzed asymmetric transcyanation of aliphatic aldehydes with acetone cyanohydrin

The vanadium(V)(salalen) complex prepared in situ from the corresponding vanadium(IV) complex 4 under aerobic conditions was found to be an excellent catalyst for asymmetric transcyanation of aliphatic aldehydes with acetone cyanohydrin as the cyanide sou

Efficient biocatalytic synthesis of (R)-pantolactone

Screening for stereoselective cyanohydrin synthesis in 96-well plates was employed in the development of an efficient, pH-stable hydroxynitrile lyase for the conversion of sterically hindered aliphatic aldehydes. Site-saturation mutagenesis (SSM) resulted in a powerful catalyst for the stereoselective conversion of hydroxypivalaldehyde and pivalaldehyde to their corresponding (R)-cyanohydrins (ee >97%) which are used as chiral building blocks (e.g., for pantothenic acid production). Furthermore, redesigning the PaHNL5 gene and improving its expression by Pichia pastoris with the help of a new P AOX1 promoter variant and the helper protein PDI (protein disulfide isomerase) led to elevated amounts of today's most efficient biocatalyst for vitamin B5 synthesis.

[Ru(phgly)2(binap)]/Li2CO3: A Highly Active, Robust, and Enantioselective Catalyst for the Cyanosilylation of Aldehydes

The right combination: A series of aromatic, heteroaromatic, aliphatic, and α,β-unsaturated aldehydes can be converted into the desired silylated cyanohydrins by reaction with (CH3)3SiCN and a catalyst system consisting of the combination of a chiral ruthenium complex and Li2CO3 (see scheme). The reaction is highly enantioselective and affords the R products with up to 98% ee within 24 h at a substrate-tocatalyst ratio of 10000:1. (Chemical Equation Presented).

Asymmetric addition of trimethylsilyl cyanide to aldehydes promoted by chiral polymeric vanadium(V) salen complex as an efficient and recyclable catalyst

The asymmetric addition of trimethylsilyl cyanide to various aldehydes catalyzed by efficient new vanadyl polymeric salen complexes having 12 repeating salen units was investigated at room temperature. An excellent yield of the trimethylsilylether of cyanohydrins (up to 98%) with high chiral induction (96%) in case of 2-methylbenzaldehyde was achieved in 18 h. The catalyst recovered four times with retention of its performance.