4‐(Trifluoromethyl)pyrimidin‐2(1H)‐ones react with trimethylsilyl cyanide in the presence of a tertiary amine catalyst to give Michael‐like 1,4‐conjugate hydrocyanation adducts exclusively at the 3,6‐positions. The resulting 2‐oxo‐6‐(trifluoromethyl)‐1,2,3,4‐tetrahydropyrimidine‐4‐carbonitriles have been used to synthesize new trifluoromethylated 4,5‐dihydroorotic acid analogues and their esters in racemic as well as enantiopure forms by a chiral auxiliary approach. The orthogonal intramolecular C–F···C=O interaction between the fluorine atom of the CF3 group and the carbon atom of the ester group observed in the crystal state may stabilize the sterically unfavourable conformation of the methyl 2‐oxo‐6‐(trifluoromethyl)hexahydropyrimidine‐4‐carboxylate molecule with axially oriented substituents.

Synthesis of Trifluoromethylated Analogues of 4,5-Dihydroorotic Acid. -(SUKACH*, V. A.; RESETNIC, A. A.; TKACHUK, V. M.; LIN, Z.; KORTZ, U.; VOVK, M. V.; ROESCHENTHALER, G.-V.; Eur. J. Org. Chem. 2015, 6, 1290-1301, http://dx.doi.org/10.1002/ejoc.201403495 ; Inst. Org. Chem., Acad. Sci. Ukr., Kiev 02660, Ukraine; Eng.) -Nuesgen 26-220