139683-93-5Relevant articles and documents
One-pot combination of enzyme and Pd nanoparticle catalysis for the synthesis of enantiomerically pure 1,2-amino alcohols
Schrittwieser, Joerg H.,Coccia, Francesca,Kara, Selin,Grischek, Barbara,Kroutil, Wolfgang,D'Alessandro, Nicola,Hollmann, Frank
, p. 3318 - 3331 (2013/12/04)
One-pot combinations of sequential catalytic reactions can offer practical and ecological advantages over classical multi-step synthesis schemes. In this context, the integration of enzymatic and chemo-catalytic transformations holds particular potential for efficient and selective reaction sequences that would not be possible using either method alone. Here, we report the one-pot combination of alcohol dehydrogenase-catalysed asymmetric reduction of 2-azido ketones and Pd nanoparticle-catalysed hydrogenation of the resulting azido alcohols, which gives access to both enantiomers of aromatic 1,2-amino alcohols in high yields and excellent optical purity (ee >99%). Furthermore, we demonstrate the incorporation of an upstream azidolysis and a downstream acylation step into the one-pot system, thus establishing a highly integrated synthesis of the antiviral natural product (S)-tembamide in 73% yield (ee >99%) over 4 steps. Avoiding the purification and isolation of intermediates in this synthetic sequence leads to an unprecedentedly low ecological footprint, as quantified by the E-factor and solvent demand.
Large-scale synthesis of (R)-2-amino-1-(2-furyl)ethanol via a chemoenzymatic approach
Purkarthofer, Thomas,Pabst, Thomas,Van Den Broek, Cor,Griengl, Herfried,Maurer, Oliver,Skranc, Wolfgang
, p. 618 - 621 (2012/12/22)
A two-step chemoenzymatic synthesis of (R)-2-amino-1-(2-furyl)ethanol for laboratory production was developed followed by successful up-scaling to kilogram scale. The generation of the asymmetric centre was accomplished by a highly enantioselective cyanohydrin reaction of furan-2-carbaldehyde with hydrocyanic acid catalyzed by the hydroxynitrile lyase from Hevea brasiliensis. Subsequent sodium borohydride reduction furnished the desired product with an enantiomeric excess of higher than 99.5%. This procedure can be considered a convenient general route for the stereoselective synthesis of ethanol amine derivatives underlining the role of biocatalysis for the generation of stereogenic centres in the synthesis of chiral intermediates.