135415-89-3Relevant articles and documents
Synthesis of aliphatic and α-halogenated ketone cyanohydrins with the hydroxynitrile lyase from Manihot esculenta
Diebler, Johannes,Von Langermann, Jan,Mell, Annett,Hein, Martin,Langer, Peter,Kragl, Udo
, p. 987 - 991 (2014/05/06)
The potential of the hydroxynitrile lyase from Manihot esculenta towards ketone substrates was investigated. It was observed that the length of the aliphatic chain is a key parameter for the conversion of aliphatic, non-branched ketones. Smaller substrates are readily converted with high enantioselectivites, but the elongation of the chain length causes a significant loss in enzyme activity. For a number of halogenated, herein especially fluorinated, acetophenone derivatives the corresponding cyanohydrins have been synthesized with good to moderate enantioselectivities. Overcoming limitations: Ketone cyanohydrins are extremely useful intermediates for the synthesis of unusual tertiary alcohols. In this contribution, the limits of the hydroxynitrile lyase from Manihot esculenta towards such substrates are investigated and evaluated. High enantioselectivities are obtained in a simple two-phase system, even with very challenging fluorinated acetophenone derivatives.
Stereoselective substitution of (R)-2-(sulfonyloxy)nitriles with sulfur nucleophiles
Effenberger, Franz,Gaupp, Sebastian
, p. 1765 - 1775 (2007/10/03)
Optically active 2-(4-toluenesulfonyloxy)-and (4- nitrobenzenesulfonyloxy)nitriles (R)-3 and (R)-4, which were obtained from (R)-cyanohydrins (R)-2 by sulfonylation, react with sulfur nucleophiles such as potassium thioacetate, potassium ethylxanthogenate, potassium thiocyanate, as well as thioalcohols and thiophenol in a typical S(N02 manner to give the (S)-2-sulfanyl nitriles (S)-7-9 and (S)-11-13 in good chemical yields and enantiomeric excesses. Even (R)-2-methyl-2-(methanesulfonyloxy)hexanenitrile (R)-6, derived from ketone cyanohydrin (R)-5, reacts with potassium thioacetate to yield (S)-2-acetylthio-2-methylhexanenitrile (S)-10 with 97% ee.
Synthesis of (R)-cyanohydrins by crude (R)-oxynitrilase-catalyzed reactions in micro-aqueous medium
Han, Shiqing,Lin, Guoqiang,Li, Zuyi
, p. 1835 - 1838 (2007/10/03)
In diisopropyl ether or ethyl acetate under micro-aqueous conditions, the enantioselective synthesis of (R)-cyanohydrins from aldehydes and methyl ketones was studied using crude (R)-oxynitrilase prepared from almonds. This reaction system performed well