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Substituent-Driven Selective N-/O-Alkylation of 4-(Trihalomethyl)pyrimidin-2(1H)-ones Using Brominated Enones
Mateus Mittersteiner1,2, Genilson S Pereira1, Yuri Silva1
1Núcleo de Química de Heterociclos (NUQUIMHE), Departamento de Química, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil.
Abstract:
The selective N- or O-alkylation of 4-(trihalomethyl)pyrimidin-2(1H)-ones, using 5-bromo enones/enaminones as alkylating agents, is reported. It was found that the selectivity toward the N- or O-regioisomer is driven by the substituent present at the 6-position of the pyrimidine ring, thus enabling the preparation of each isomer as the sole product, in 60-95% yields. Subsequent cyclocondensation of the enaminone moiety with nitrogen dinucleophiles led to pyrimidine-azole conjugates in 55-83% yields.
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