SYNTHESIS OF PYRIDINYLKETONES, AND THEIR CYCLIC DERIVATIVES
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Parameters of the 1Н NMR (DMSO-d6) and mass spectra for compounds II, IV–VII
Comp. no.
Mass-spectrum, m/z (Irel, %)
248(100), 233(5), 220(10), 205(6), 14.16 s (1Н, NH), 13.84 s (1Н, NH), 6.03 s (1Н, CH), 6.41 s (4Н, СН2), 2.30 s (3Н,
192(9), 179(8), 164(27), 151(74) СН3), 1.00 s (6Н, СН3)
228(39), 200(18), 151(37), 105 14.40 s (1Н, NH), 11.74 s (1Н, NH), 7.65–7.47 m (5Н, СНarom), 5.80 s (1Н, СН), 5.66
(100), 84(32), 77(90) s (1Н, СН), 2.23–2.15 m (3Н, СН3)
1Н NMR (DMSO-d6) spectrum, δ, ppm
II
IVа
308(30), 306(33), 280(8), 278(10), 14.27 s (1Н, NH), 11.80 s (1Н, NH), 7.70 m (4Н, СНarom), 5.76 s (1Н, СН), 5.67 s
185(98), 183(100), 157(37), 155 (1Н, СН), 2.23 s (3Н, СН3)
IVb
(39), 151(90), 84(95)
450(64), 432(8), 345(38), 341(280), 11.50 s (2Н, 2NH), 7.56–7.20 m (10Н, СНarom), 5.85 s (1Н, СН), 5.58 s (1Н, СН),
262(7), 235(29), 105(100), 8(14), 77(52) 3.40 s (2Н, СН2), 2.36 s (3Н, СН3), 1.98 s (3Н, СН3)
Va
Vbа
VIa
608(26), 590(10), 562(9), 423(16), 11.56 br.s (1Н, NH), 10.98 s (1Н, NH), 7.46–7.16 m (8Н, СНarom), 5.87 s (1Н, СН),
183(100), 155(28)
5.67 s (1Н, СН), 3.59 s (2Н, СН2), 2.37 s (3Н, СН3), 2.10 s (3Н, СН3)
346(4), 318(2), 241(50), 224(6), 105 12.60 br.s (1Н, NH), 8.03–7.54 m (10Н, СНarom), 6.05 s (1Н, СН), 5.28 d.d (1Н,
(100), 77(35)
CHСН2, J 8.1, J 5.1 Hz), 3.91 d.d (1Н, CHСН2, J 19.2, J 8.1 Hz), 3.71 d.d (1Н,
CHСН2, J 19.2, J 5.1 Hz), 2.02 s (3Н, СН3)
425(2), 397(1), 320(2), 302(3), 241 12.64 br.s (1Н, NH), 8.03–7.53 m (9Н, СНarom), 6.06 s (1Н, СН), 5.27 d.d (1Н,
(53), 213(16), 185(7), 157(5), 105 CHСН2, J 8.1, J 5.1 Hz), 3.96 d.d (1Н, CHСН2, J 19.2, J 8.1 Hz), 3.72 d.d (1Н,
VIb
VII
(100), 77(33)
CHСН2, J 19.2, J 5.1 Hz), 2.01 s (3Н, СН3)
328(73), 105(100), 77(22)
12.55 br.s (1Н, NH), 7.86–7.41 m (11Н, СНarom), 6.20 s (1Н, СН), 2.22 s (3Н, СН3)
a 1Н NMR spectra were taken in CDCl3 solution.
filtered off, dried, and crystallized from ethanol. Yield
0.7 g (57%), mp 186°C. Found, %: C 62.81; H 6.57; N
11.21. С13Н16N2O3. Calculated, %: C 62.89; H 6.50; N
11.28.
carried out using 3.38 g of compound IIIb to obtain
thiouracil I (0.67 g, 47%) and (Е,Z)-2-[2-(4-bromo-
phenyl)-2-оxoethylidene]-6-methyl-2,3-dihydropyri-
midin-4(1Н)-one (IVb) [0.28 g (9%), mp 168–170°C.
Found, %: C 68.48, H 5.36; N 12.21. С13Н11BrN2O2.
Calculated, %: C 50.84, H 3.61; N 9.12.
Thermolysis of 6-methyl-2-(2-oxo-2-phenylethyl-
thio)pyrimidin-4(3H)-one (IIIa). Compound IIIa
(2.6 g) was heated with stirring at 180–200°C to form
a melt, followed by its solidification. The cooled mass
was extracted with chloroform, undissolved residue
was filtered off, washed with chloroform to discolora-
tion, and dried on air. Yield 0.63 g (44%). Chloroform
was evaporated at a reduced pressure. The residue was
purified by column chromatography (eluent chloro-
form) to give (Е,Z)-6-methyl-2-(2-oxo-2-phenylethyl-
idene)-2,3-dyhydropyrimidin-4(1Н)-one (IVа). Yield
0.26 g (12%), mp 250–252°C. Found, %: C 68.48, H
5.36; N 12.21. С13Н12N2O2. Calculated, %: C 68.41, H
5.30; N 12.27. When chloroform–acetonitrile mixture
(1:1) was used as eluent, 8-benzoyl-4-methyl-7-[(4-
methyl-6-oxo-1,6-dihydropyrimidin-2-yl)methyl]-6-
phenylpyrrole[1,2-а]pyrimidin-2(1Н)-one (Va) was
obtained. Yield 0.32 g (21%), mp 168–170°C. Found,
%: C 72.11; H 5.12; N 12.37. C27H22N4О3. Calculated,
%: 71.99; H 4.92; N 12.44.
8-(4-Bromobenzoyl)-6-(4-bromophenyl)-4-methyl-
7-[(4-methyl-6-oxo-1,6-dihydropyrimidin-2-yl)methyl]-
pirrole[1,2-а]pyrimidin-2(1Н)-one (Vb). Yield 0.98 g
(16%), mp > 220ºC (decomp.) Found, %: C 53.22; H
3.34; N 9.14. С27Н20Br2N4O3. Calculated, %: C 53.29;
H 3.29; N 9.21.
(Е,Z)-6-Methyl-2-(2-oxo-2-phenylethylidene)-2,3-
dihydropyrimidin-4(1Н)-one (IVа). A mixture of 0.5 g
of compound IIIa in 25 ml of DMF and 0.5 g of PPh3
was refluxed for 6 h. After cooling the mixture was
poured into 100 ml of water. The resulting precipitate
was filtered off, dried, and washed with hot benzene to
remove the phosphorus compounds. The residue was
crystallized from ethanol. Yield 0.34 g (86%), mp 250–
252°C. Found, %: C 68.48; H 5.36; N 12.21.
С13Н12N2O2. Calculated, %: C 68.41; H 5.30; N 12.27.
2-(4-Methyl-6-oxo-1,6-dihydropyrimidin-2-yl)-
1,4-diphenylbutane-1,4-dione (VIa). A mixture of
2.3 g compound IVa and 0.4 g of NaOH was dissolved
in a minimal amount of 50% aqueous dioxane. To the
Thermolysis of 2-[2-(4-bromophenyl)-2-oxoethyl-
thio]-6-methylpyrimidin-4(3H)-one (IIIb) was similarly
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 82 No. 4 2012