01588nas a2200229   4500008004100000022001400041245016600055210006900221260010600290300001400396490000700410520065900417653003401076653001601110653001501126653001401141653001001155100001801165700002901183700002201212856012401234       2007                        eng d  a0040-403900aNaIO4-mediated asymmetric bromohydroxylation of alpha,beta-unsaturated carboxamides with high diastereoselectivity: a short route to (-)-cytoxazone and droxidopa0 aNaIO4mediated asymmetric bromohydroxylation of alphabetaunsatura  aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLANDbPERGAMON-ELSEVIER SCIENCE LTDcFEB  a1375-13780 v483 a<p>The NaIO4-mediated asymmetric bromohydroxylation of alpha,beta-unsaturated carboxamides was achieved using lithium bromide as the bromine source under acidic conditions at rt to afford the corresponding chiral alpha-bromo-beta-hydroxy carboxamides. Excellent yields (77-90%) and diastereoselectivities (up to 10:1) along with exclusive control over regio- as well as anti-selectivity are the main features with a good scope of substrates. The method has successfully been applied in the enantioselective syntheses of two biologically important molecules, viz (-)-cytoxazone and L-threo-DOPS (droxidopa). (c) 2007 Elsevier Ltd. All rights reserved.</p>10aasymmetric bromohydroxylation10aCarboxamide10acytoxazone10adroxidopa10aNaIO41 aGeorge, Shyla1 aNarina, Srinivasarao, V.1 aSudalai, Arumugam  uhttps://library.ncl.res.in/content/naio4-mediated-asymmetric-bromohydroxylation-alphabeta-unsaturated-carboxamides-high