Methyl 6-methyl-2-oxo-4-phenyl-1,2,3,4-tetrahydropyrimidine-5-carboxylate (1): white solid (0.80 g, 81% yield) M.p. 212-213 °C (lit. 212-214 °C).
1H NMR (400 MHz, DMSO-d6): δ 2.23 (s, 3H), 3.51 (s, 3H), 5.12 (s, 1H), 7.20-7.32 (m, 5H), 7.76 (s, 1H), 9.23 (s, 1H).
13C NMR (100 MHz, DMSO-d6): δ 18.29, 51.27, 54.21, 99.40, 126.61, 127.76, 128.92, 145.10, 149.15, 152.63, 166.28.
Methyl 4-(4-bromophenyl)-6-methyl-2-oxo-1,2,3,4-tetrahydropyrimidine-5-carboxylate (2): pale yellow powder (0.74 g, 57%)
M.p. 221-222 °C (lit. 218-220 °C)
.
1H NMR (400 MHz, DMSO-d6): δ 2.23 (s, 3H), 3.51 (s, 3H), 5.10 (s, 1H), 7.16 (d, 2H), 7.51 (d, 2H), 7.79 (s, 1H), 9.28 (s, 1H).
13C NMR (100 MHz, DMSO-d6): δ 18.31, 51.32, 53.75, 98.94, 120.82, 128.94, 131.84, 144.44, 149.50, 152.41, 166.14.
Methyl 4-(4-methoxyphenyl)-6-methyl-2-oxo-1,2,3,4-tetrahydropyrimidine-5-carboxylate (3): white yellow-ish solid (0.71 g, 68 %)
M.p. 197.5-198.3°C (lit. 190-191 °C)
.
1H NMR (400 MHz, DMSO-d6): δ 2.22 (s, 3H), 3.50 (s, 3H), 3.70 (s, 3H), 5.06 (s, 1H), 6.85 (d, 2H), 7.12 (d, 2H), 7.69 (s, 1H), 9.18 (s, 1H).
13C NMR (100 MHz, DMSO-d6): δ 18.26, 51.24, 55.49, 99.68, 114.21, 127.78, 137.28, 148.83, 152.61, 158.89, 166.31.