title: Development of an efficient route to CF3-substituted pyrrolopyrimidines through understanding the competition between Michael and aza-Henry reactions.
abstract: The regioselective base-catalyzed addition of nitromethane to 2-oxo-4-trifluoromethyl-1,2-dihydropyrimidine-5-carboxylates is reported. It was found that the Michael-like pathway is highly reversible and substantially dominating under conditions of kinetic control (0-5 °C, 10 h) whereas the aza-Henry reaction leads to thermodynamically stable adducts after 8-24 h exposure at room temperature. The adjacent nitro and alkoxycarbonyl groups were exploited to demonstrate the synthetic potential of the obtained products by converting to the isomeric trifluoromethylated pyrrolo[3,4-d]pyrimidine-2,5-diones. With this aim an efficient protocol for selective reduction of nitro-derivatives to the corresponding 4- or 6-aminomethyl-2-oxo-4-trifluoromethyl-1,2,3,4-tetrahydropyrimidine-5-carboxylates and their subsequent thermal cyclocondensations was applied.
authors.affiliation: Institute of Organic Chemistry, National Academy of Sciences of Ukraine, Murmanskaya str. 5, Kyiv, 02660, Ukraine. vsukach@gmail.com.
authors.forename: V M
authors.initials: VM
authors.lastname: Tkachuk
authors.forename: V A
authors.initials: VA
authors.lastname: Sukach
authors.forename: K V
authors.initials: KV
authors.lastname: Kovalchuk
authors.forename: M V
authors.initials: MV
authors.lastname: Vovk
authors.forename: V G
authors.initials: VG
authors.lastname: Nenajdenko