1597414-44-2Relevant academic research and scientific papers
Control of regio- and enantioselectivity in the asymmetric organocatalytic addition of acetone to 4-(trifluoromethyl)pyrimidin-2(1H)-ones
Sukach, Volodymyr A.,Tkachuk, Viktor M.,Shoba, Veronika M.,Pirozhenko, Volodymyr V.,Rusanov, Eduard B.,Chekotilo, Alexey A.,Roeschenthaler, Gerd-Volker,Vovk, Mykhailo V.
supporting information, p. 1452 - 1460 (2014/03/21)
The reactions of variously substituted 4-(trifluoromethyl)pyrimidin-2(1H)- ones with acetone in the presence of L-proline or chiral secondary amine organocatalysts were studied. As demonstrated, 4-(trifluoromethyl)pyrimidin- 2(1H)-ones unsubstituted at the 6-position of the heterocyclic ring react with acetone at the endocyclic C=N or C=C bond depending on whether thermodynamic or kinetic control is operative in the addition reaction and also depending on the catalyst used. Racemic kinetically preferred regioisomers, 6-(2-oxopropyl)-4- (trifluoromethyl)-3,4-dihydropyrimidin-2(1H)-ones, were found to undergo intermolecular organocatalytic rearrangement into enantioenriched thermodynamically stable products, 4-(2-oxopropyl)-4-(trifluoromethyl)-3,4- dihydropyrimidin-2(1H)-ones, with enantiomeric ratios up to 83:17. Chiral-amine-catalyzed reactions of simple 4-(trifluoromethyl)ated pyrimidones with acetone represent a general equilibrium system in which Michael-like adducts are formed reversibly under kinetic control and Mannich-like adducts are thermodynamically stable. Only the latter products are obtainable in the enantioenriched form, with up to 83:17 er. Copyright
