125850-19-3Relevant articles and documents
Enzyme-catalysed regio- and enantioselective preparative scale synthesis of (S)-2-hydroxy alkanones
Loderer,Ansorge-Schumacher
, p. 38271 - 38276 (2015)
α-Hydroxy alkanones were synthesised with high enantiomeric purity by stereoselective enzyme-catalysed diketone reduction. Both diketone reduction and cofactor regeneration were accomplished with purified carbonyl reductase from Candida parapsilosis (CPCR2). The reaction products were isolated by column chromatography and analysed by chiral GC measurements, 1H-NMR spectroscopy and determination of optical rotations. Preparative-scale biotransformations yielded 350-600 mg of pure aliphatic α-hydroxy ketones including the difficult to obtain (S)-2-hydroxypentane-3-one. For all the products good enantiomeric excesses in the range of 89-93% were achieved.
Promiscuous substrate binding explains the enzymatic stereoand regiocontrolled synthesis of enantiopure hydroxy ketones and diols
Kurina-Sanz, Marcela,Bisogno, Fabricio R.,Lavandera, Ivan,Orden, Alejandro A.,Gotor, Vicente
experimental part, p. 1842 - 1848 (2011/02/25)
Regio- and stereoselective reductions of several diketones to afford enantiopure hydroxy ketones or diols were accomplished using isolated alcohol dehydrogenases (ADHs). Results could be rationalised taking into account different (promiscuous) substrate-binding modes in the active site of the enzyme. Furthermore, interesting natural cyclic diketones were also reduced with high regio- and stereoselectivity. Some of the 1,2 and 1,3-diketones used in this study were reduced by employing a low excess of the hydrogen donor (2-propanol) due to the quasi-irreversibility of these ADH-catalysed processes. Thus, using lower quantities of co-substrate, scale-up could be easily achieved.
107. Silicon-Directed Regio- and Enantioselective Synthesis of α-Hydroxy-ketones
Lohray, Braj B.,Enders, Dieter
, p. 980 - 984 (2007/10/02)
α-Silylated ketones (S)-2 (ee >/= 98percent), easily available through silylation or silylation/alkylation from ketones 1 using the (-)-(S)-1-amino-2-(methoxymethyl)pyrrolidine (SAMP)-/(+)-(R)-1-amino-2-(methoxymethyl)pyrrolidine (RAMP)-hydrazone method, are oxidized to give α-hydroxy-ketones (R)-5 of high enantiomeric purity (ee >/= 98percent) and in good overall yields (51-70percent).The key step of the procedure is the silicon-directed diastereoselective oxidation of the corresponding silyl enol ethers of (S)-2, with m-chloroperbenzoic acid or 3-phenyl-2-(phenylsulfonyl)oxaziridine, followed by flash chromatography and desilylation.