139765-19-8

Upstream product

• 151-50-8 potassium cyanide 
• 104-88-1 4-chlorobenzaldehyde 
• 18162-48-6 tert-butyldimethylsilyl chloride 
• 56522-24-8 tert-butyldimethylsilyl cyanide 
• 13312-83-9 4-chloromandelonitrile 
• 69739-34-0 t-butyldimethylsiyl triflate 

Downstream Products

• 13312-83-9 (R)-(+)-4-chloromandelonitrile 
• 13312-83-9 (2S)-2-hydroxy-2-(4-chlorophenyl)acetonitrile 

Relevant academic research and scientific papers

One-Pot Synthesis of Optically Active Cyanohydrin Acetates from Aldehydes via Quinidine-Catalyzed Transhydrocyanation Coupled with Lipase-Catalyzed Kinetic Resolution in Organic Solvent

A novel one-pot synthetic method was developed for the preparation of optically active cyanohydrin acetates.Racemic cyanohydrins were generated from aldehydes and acetone cyanohydrin by quinidine-catalyzed transhydrocyanation, and the resulting cyanohydrins 2a-j were then acetylated by lipase in a stereoselective manner using isopropenyl acetate as an acylating reagent.A variety of aldehydes 1a-j were successfully transformed into the corresponding cyanohydrin acetates 3a-j having 47-95percent e.e. without isolating the unstable cyanohydrins 2.Moreover, the reversible nature of base-catalyzed transhydrocyanation allows for in situ racemization of the unreacted cyanohydrins and concurrent kinetic resolution by lipase enabled the preparation of (S)-3b-d with 40-82percent e.e. in more than 50percent yield.Polymer-supported cinchona alkaloid was also used as a catalyst for this one-pot reaction and showed the comparable chemical and optical yield to that for the soluble monomeric alkaloid.The insoluble polymer and lipase were recovered by filtration and found to have almost the same catalytic activity even after four times of reuse.

P(RNCH2CH2)N: Efficient catalysts for the cyanosilylation of aldehydes and ketones

The 1,2-addition of trialkylsilylcyanides to aldehydes and ketones produces the corresponding protected cyanohydrins in good to excellent yields when carried out at 0°C to room temperature in the presence of catalytic amounts of the nonionic strong base P(RNCH2CH2)N (R = Me, i-Pr) in THF. These catalysts are easily removed from the product by hydrolysis or column filtration through silica gel.

Enantioselective synthesis of protected cyanohydrins

A straightforward process for the preparation of optically active protected cyanohydrins, important building blocks for the synthesis of drugs and agrochemicals, has been established. Lipase B from Candida Antarctica (CAL-B) catalysed the kinetic resoluti