4
-(HET)ARYL-4,7-DIHYDROAZOLOPYRIMIDINES
779
4
6
.97 d and 5.04 d (1H each, PhCH , J = 12.7 Hz),
.30 s (2H, 7-H), 7.07 m (2H, Harom), 7.18 m (2H,
(1H, 2-H), 10.94 s (1H, NH). Found, %: C 56.36;
H 5.84; N 17.47. C H N O S. Calculated, %:
2
15
18
4
2
Harom), 7.27 m (6H, Harom), 7.65 s (1H, 2-H), 10.88 br.s
C 56.41; H 5.79; N 17.53. M 318.12.
-Methyl-7-(thiophen-2-yl)-4,7-dihydro[1,2,4]-
triazolo[1,5-a]pyrimidine-6-carboxamide (8d). Yield
8%, white powder, mp 247–250°C. IR spectrum, ν,
1
3
(
1H, NH). C NMR spectrum, δ , ppm: 18.54 (CH ),
C 3
5
7
6
5
1
1
9.37 (C ), 64.95 (CH ), 96.63 (C ), 127.01, 127.47,
2
27.64, 127.92, 128.19, 128.40, 136.28, 141.84 (Carom),
2
5
3a
2
46.76 (C ), 147.56 (C ), 150.13 (C ), 164.85 (C=O).
–1
cm : 3262 (NH), 3165 (C–Harom), 2913 (C–Haliph),
Found, %: C 69.29; H 5.23; N 16.23. C H N O . Cal-
20
18
4
2
1
1
665 (C=O), 1751 (C=N), 1594 (δNH), 1556 (C=C),
300, 808. H NMR spectrum, δ, ppm: 2.22 s (3H,
culated, %: C 69.35; H 5.24; N 16.17. M 346.39.
1
Benzyl 5-methyl-7-phenyl-4,7-dihydro[1,2,4]tri-
azolo[4,3-a]pyrimidine-6-carboxylate (7e). Yield
5-CH
(1H, HTh), 7.26 br.s (2H, NH
1.09, 5.04 Hz), 7.64 s (1H, 2-H), 10.18 s (1H, NH).
3
), 6.72 s (1H, 7-H), 6.93 m (1H, HTh), 7.00 m
), 7.43 d.d (1H, HTh, J =
2
3
%, white powder, mp 203–204°C. IR spectrum, ν,
–
1
13
7
cm : 3136 (NH), 2858 (C–Haliph), 1704 (C=O), 1649
C=C), 1282, 1262 (C–N), 1581, 1418, 1541, 1497,
C NMR spectrum, δ
C
, ppm: 17.46 (CH
3
), 54.86 (C ),
6
(
102.21 (C ), 125.89, 126.32, 126.54, 137.68 (CTh),
1
5
3a
2
7
4
6
58. H NMR spectrum, δ, ppm: 2.45 s (3H, 5-CH ),
144.38 (C ), 147.45 (C ), 149.86 (C ), 167.61 (C=O).
Found, %: C 50.70; H 4.32; N 26.75. C11 OS.
3
.96 d and 5.02 d (1H each, PhCH , J = 12.7 Hz),
H N
11 5
2
.40 s (1H, 7-H), 7.07 m (2H, Harom), 7.27 m (8H,
Calculated, %: C 50.59; H 4.36; N 26.70. M 261.07.
1
3
Harom), 8.17 s (1H, 2-H), 10.86 br.s (1H, NH). C NMR
Benzyl 5-methyl-7-(thiophen-2-yl)-4,7-dihydro-
[1,2,4]triazolo[1,5-a]pyrimidine-6-carboxylate (8e).
Yield 0.758 g (47%), white powder, mp 207–209°C.
7
spectrum, δ , ppm: 18.76 (CH ), 55.69 (C ), 64.89
C
3
6
(
1
(
CH ), 95.02 (C ), 126.58 127.48, 127.66, 128.14,
28.20, 128.74 (C ), 136.32 (C ), 138.78, 142.33
arom
Carom), 146.53 (C ), 148.27 (C ), 164.72 (C=O).
2
1
–
1
IR spectrum, ν, cm : 3140 (NH), 2865 (C–Haliph),
3
a
5
1695 (C=N), 1650 (C=C), 1582, 1547, 1497, 1412,
1
Found, %: C 69.19; H 5.17; N 16.19. C H N O . Cal-
20
18
4
2
1298, 1253 (C–N), 745. H NMR spectrum, δ, ppm:
culated, %: C 69.35; H 5.24; N 16.17. M 346.39.
2
.43 s (3H, 5-CH ), 5.05 d and 5.11 d (1H each,
3
PhCH , J = 12.8 Hz), 6.63 s (1H, 7-H), 6.92 d (2H,
Methyl 5-methyl-7-(thiophen-2-yl)-4,7-dihydro-
1,2,4]triazolo[1,5-a]pyrimidine-6-carboxylate (8b).
2
H ), 7.15 m (2H, Harom), 7.28 m (3H, Harom), 6.92 t
[
Th
(
1H, H , J = 3.2 Hz), 7.72 s (1H, 2-H), 10.99 s (1H,
Yield 78%, yellow crystals, mp 245–246°C. IR spec-
Th
–
1
NH). Found, %: C 61.46; H 4.67; N 15.89; S 9.14.
C H N O S. Calculated, %: C 61.35; H 4.58;
trum, ν, cm : 3284 (NH), 3136 (C–Harom), 2795
(
(
C–Haliph), 1698 (C=O), 1650, 1784 (C=N), 1551, 1585
18 16
4
2
1
N 15.90; S 9.10. M 354.42.
C=C), 1296 (O–C), 979 (N–N), 735. H NMR spec-
trum, δ, ppm: 2.41 s (3H, 5-CH ), 3.58 s (3H, OCH ),
Benzyl 5-methyl-7-(thiophen-3-yl)-4,7-dihydro-
[1,2,4]triazolo[1,5-a]pyrimidine-6-carboxylate (8f).
Yield 0.532 g (33%), white powder, mp 232–233°C.
3
3
6
7
.59 s (1H, 7-H), 6.93 m (2H, H ), 7.40 m (1H, H ),
.73 s (1H, 2-H), 10.95 s (1H, NH). C NMR spec-
Th Th
13
–
1
trum, δ , ppm: 18.43 (5-CH ), 51.03 (OCH ), 54.16
IR spectrum, ν, cm : 3139 (NH), 2869 (C–Haliph),
C
3
3
7
6
(
1
C ), 96.93 (C ), 125.30, 125.88, 126.84, 145.16 (C ),
46.94 (C ), 147.33 (C ), 150.26 (C ), 165.46 (C=O).
1695 (C=N), 1645 (C=C), 1584, 1549, 1442, 1421,
Th
5
3a
2
1
1294, 1252 (C–N), 764. H NMR spectrum, δ, ppm:
Found, %: C 52.48; H 4.39; N 20.27; S 11.58.
C H N O S. Calculated, %: C 52.16; H 4.37;
2.41 s (3H, 5-CH ), 5.03 d and 5.12 d (1H each,
3
PhCH , J = 12.8 Hz), 6.43 s (1H, 7-H), 6.88 d.d
1
2
12
4
2
2
N 20.24; S 11.69. M 276.07.
(1H, HTh, J = 5.0, 1.3 Hz), 7.14 m (2H, HTh), 7.28 m
(
7
4H, Harom), 7.42 d.d (1H, Harom, J = 5.0, 2.9 Hz),
2
-Methylpropyl 5-methyl-7-(thiophen-2-yl)-4,7-
1
3
.69 s (1H, 2-H), 10.86 s (1H, NH). C NMR spec-
dihydro[1,2,4]triazolo[1,5-a]pyrimidine-6-carbox-
ylate (8c). Yield 45%, yellowish crystals, mp 188–
90°C. IR spectrum, ν, cm : 3368 (NH), 3119
C–Harom), 2869, 2954 (C–Haliph), 1692 (C=O), 1793
C=N), 1583 (C=C), 1303 (O–C), 979 (N–N), 784.
H NMR spectrum, δ, ppm: 0.75 d.d [6H, (CH ) CH,
7
trum, δ , ppm: 18.51 (CH ), 54.36 (C ), 64.92
(CH ), 96.47 (C ), 122.95, 126.36, 126.67, 127.38,
1
(
Found, %: C 61.45; H 4.58; N 15.89; S 9.00.
C H N O S. Calculated, %: C 61.35; H 4.58;
N 15.90; S 9.10. M 354.42.
C
3
6
–
1
2
1
(
27.65, 128.27, 136.44, 142.73 (C , C ), 146.88
arom Th
5
3a
2
C ), 147.58 (C ), 150.09 (C ), 164.88 (C=O).
(
1
3
2
1
8
16
4
2
J = 0.74, 7.44 Hz], 1.77 m [1H, (CH ) CH], 2.44 s
3H, 5-CH ), 3.78 m (2H, OCH ), 6.59 s (1H, 7-H),
3
2
(
3 2
6
.93 d.d (1H, H , J = 5.02, 5.01 Hz), 6.96 m (1H,
Azolopyrimidines 9 and 10 (general procedure).
A solution of 0.3 g (1 mmol) of compound 2 or 6d in
Th
H ), 7.41 d.d. (1H, H , J = 5.02, 5.01 Hz), 7.72 s
Th
Th
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 55 No. 6 2019