Paper
RSC Advances
22 P. Das, A. Dutta, A. Bhaumik and Ch. Mukhopadhyay, Green
Chem., 2014, 16, 1426.
23 F. Matloubi-Moghaddam, M. Doulabi and H. Saeidian, Sci.
Iran., 2012, 19, 1597.
24 M. M. Heravi, A. Ghods, F. Derikvand, K. Bakhtiari and
F. F. Bamoharram, J. Iran. Chem. Soc., 2010, 7, 615.
25 D. Prajapati and M. Gohain, Beilstein J. Org. Chem., 2006, 2, 1.
26 I. H. Gul, W. Ahmed and A. Maqsood, J. Magn. Magn. Mater.,
2008, 320, 270.
27 N. M. Deraz and A. Alari, Int. J. Electrochem. Sci., 2012, 7, 6501.
28 I. Devi, B. S. D. Kumar and P. J. Bhuyan, Tetrahedron Lett.,
2003, 44, 8307.
2,3,4,5-tetrahydro-1H-pyrano [2,3-d] pyrimidine-6-carbonitrile,
white solid; M.p: 238 C; IR (KBr, cmꢀ1) ymax ¼ 3406, 3317,
ꢁ
3198, 2929, 2194, 1707, 1692, 1639, 1489, 1387, 1230, 1185,
1045, 752; 1HNMR (400 MHz, DMSO-d6): d ¼ 3.07 (s, 3H,
NMe), 3.40 (s, 3H, NMe), 4.92 (s, 1H, CH), 7.25–7.47 (m,
5H, Ar–H and NH2); 13C NMR (100 MHz, DMSO-d6): d ¼
29.2, 30.7, 58.2, 89.4, 120, 129.9, 130.4, 130.5, 131.9,
133.1, 151.5, 153.1, 159.4, 161.9 ppm; MS: m/z ¼ 378
(M+)7-Amino-5-(3-uorophenyl)-1,3-dimethyl-2,4-dioxo-2,3,4,5-
tetrahydro-1H-pyrano [2,3-d] pyrimidine-6-carbonitrile, white
solid; M.p: 228–229 ꢁC; IR (KBr, cmꢀ1) ymax ¼ 3381, 3309,
3191, 2199, 1708, 1691, 1640, 1493, 1387, 1232, 1191, 1037,
850, 751, 572; 1H NMR (400 MHz, DMSO-d6): d ¼ 3.06 (s,
3H, NMe), 3.42 (s, 3H, NMe), 4.33 (s, 1H, CH), 7.09–7.35
(m, 6H, Ar–H and NH2); 13C NMR (100 MHz, DMSO-d6): d
¼ 29.2, 30.7, 37.4, 60, 90.2, 116.4, 116.6, 120.5, 130.8,
130.9, 135.1, 141.9, 151.5, 152.6, 159.1, 161.4, 162.0 ppm;
MS: m/z ¼ 328 (M+)7-Amino-5-(2-uorophenyl)-1,3-dimethyl-
2,4-dioxo-2,3,4,5-tetrahydro-1H-pyrano [2,3-d] pyrimidine-6-
carbonitrile, white solid; M, 2196 white solid; M.p: 238–239
ꢁC; IR (KBr, cmꢀ1) ymax ¼ 3390, 3312, 3194, 2196, 1705,
29 J. Khurana, B. Nand and P. Saluja, J. Heterocycl. Chem., 2014,
51, 618.
30 A. Azarifar, R. Nejat-Yami and D. Azarifar, J. Iran. Chem. Soc.,
2013, 10, 297.
31 G. Rui-Yun and A. Zhi-Min, ACS. Comb. Sci., 2013, 15, 557.
32 F. Seeliger and S. Berger, J. Org. Chem., 2007, 72, 9170–9180.
33 Procedure for the synthesis of spinel ZnFe2O4 nanopowder: a
solution of FeCl3$6H2O (0.2 mol Lꢀ1, 200 mL) was added
into a stirring round bottomed ask (50 mL) containing a
solution of ZnCl2 (0.1 mol Lꢀ1, 100 mL). Aer the addition
was completed, the reaction mixture was neutralized by
sodium hydroxide solution (1.5 mol Lꢀ1). The reaction
temperature was kept at 85 ꢁC for 45 min under stirring.
Aer this time, the pH of the reaction was adjusted on 12.
The precipitates were washed with distilled water until the
particles were free from sodium and chloride ions. The
product was dried in an electric oven at a temperature of
1
1687, 1641, 1490, 1390, 1235, 1192, 1039, 969, 760, 572; H
NMR (400 MHz, DMSO-d6): d ¼ 3.04 (s, 3H, NMe), 3.39 (s,
3H, NMe), 4.59 (s, 1H, CH), 7.10–7.36 (m, 6H, Ar–H and
NH2); 13C NMR (100 MHz, DMSO-d6): d ¼ 29.2, 30.7, 32,
58.7, 89.2, 116.7, 117, 120.4, 126.0, 130.4, 131.4, 132.2,
132.3, 151.5, 153, 159.5, 160.4, 161.9, 162.8 ppm; MS: m/z
¼
328 (M+)7-Amino-5-(4-chloro-3-nitrophenyl)-1,3-dimethyl-
2,4-dioxo-2,3,4,5-tetrahydro-1H-pyrano [2,3-d] pyrimidine-6-
carbonitrile, white solid; M.p: 209–210 ꢁC; IR (KBr, cmꢀ1
800 C for 3 h to remove water contents.27
)
ꢁ
34 General procedure for the synthesis of pyrano[2,3-d]
pyrimidines: to a mixture of 1,3-dimethylbarbituric acid (1
mmol), malononitrile (1.2 mmol) and aromatic aldehyde (1
mmol) in a test tube ZnFe2O4 nanoparticles (0.0125 g, 5
mol%) was added and the resulting mixture was stirred in
an oil-bath at 75 ꢁC for the appropriate time. Aer
completion of the reaction, as monitored by TLC, ethanol
was added and the mixture stirred for 5 min. The
magnetic ZnFe2O4 nanoparticles were separated from the
products using an external magnet and then washed twice
with acetonitril, dried in a desiccator and stored for
another subsequent reaction runs (the catalyst reused
seven times in subsequent reaction without any signicant
changes in the yield and reaction times). The solid product
was ltered, washed with acetone and dried. The pure
products (compounds 1–19) were identied by IR, 1H,
13CNMR and mass spectra.
35 7-Amino-5-(3-chlorophenyl)-1,3-dimethyl-2,4-dioxo-2,3,4,5-
tetrahydro-1H-pyrano [2,3-d] pyrimidine-6-carbonitrile, white
solid; M.p: 247–248 ꢁC; IR (KBr, cmꢀ1) ymax ¼ 3395, 3312,
3192, 2194, 1707, 1689, 1641, 1488, 1389, 1232, 1190, 1036,
750, 570; 1HNMR (400 MHz, DMSO-d6): d ¼ 3.03 (s, 3H,
NMe), 3.38 (s, 3H, NMe), 4.83 (s, 1H, CH), 7.21–7.34 (m,
6H, Ar–H and NH2); 13C NMR (100 MHz, DMSO-d6): d ¼
29.2, 30.7, 35.1, 58.7, 89.6, 120.1, 129.1, 130, 130.8, 131.80,
133.8, 142.7, 151.6, 153.1, 159.3, 161.9 ppm; MS: m/z ¼ 345
(M+), 7-Amino-5-(2,3-dichlorophenyl)-1,3-dimethyl-2,4-dioxo-
ymax ¼ 3395, 3316, 3198, 2201, 1716, 1690, 1639, 1489,
1
1392, 1231, 1186, 1047, 969, 752, 505; H NMR (400 MHz,
DMSO-d6): d ¼ 3.04 (s, 3H, NMe), 3.40 (s, 3H, NMe), 4.49
(s, 1H, CH), 7.47–7.95 (m, 5H, NH2, Ar–H); 13C NMR (100
MHz, DMSO-d6): d ¼ 29.2,30.7, 37.4, 58.7, 88.8, 120.2,
124.5, 125.7, 132.8, 134.6, 147.0, 149.3, 151.6, 153.1, 159.2,
162.1 ppm; MS: m/z ¼ 389 (M+)7-Amino-5-(2-bromophenyl)-
1,3-dimethyl-2,4-dioxo-2,3,4,5-tetrahydro-1H-pyrano
[2,3-d]
pyrimidine-6-carbonitrile, white solid; M, 2194 white solid;
M.p: 237–238 ꢁC; IR (KBr, cmꢀ1) ymax ¼ 3396, 3311, 3190,
2194, 1709, 1687, 1641, 1488, 1389, 1232, 1189, 1026, 969,
749, 567; 1H NMR (400 MHz, DMSO-d6): d ¼ 3.04 (s, 3H,
NMe), 3.34 (s, 3H, NMe), 4.85 (s, 1H, CH), 7.13–7.53 (m,
6H, NH2, Ar–H); 13C NMR (100 MHz, DMSO-d6): d ¼ 29.2,
30.7, 37.4, 58.9, 89.8, 120, 124.4, 129.7, 130.2, 131.8,
134, 144.4, 151.6, 153, 159.2, 161.9 ppm; MS: m/z ¼ 389
(M+)7-Amino-5-(2-methoxyphenyl)-1,3-dimethyl-2,4-dioxo-2,3,4,5-
tetrahydro-1H-pyrano [2,3-d] pyrimidine-6-carbonitrile, white
solid and mp 209–210 ꢁC, 2190 white solid; mp 209–210
ꢁC; IR (KBr, cmꢀ1) ymax ¼ 3483, 3311, 3172, 2962, 2190,
1715, 1680, 1642, 1489, 1382, 1229, 1188, 1020, 753, 568;
1H NMR (400 MHz, DMSO-d6): d ¼3.04 (s, 3H, NMe), 3.38
(s, 3H, NMe), 3.72 (s, 3H, CH3), 4.61 (s, 1H, CH), 6.82–7.16
(m, 6H, NH2, Ar–H); 13C NMR (100 MHz, DMSO-d6): d ¼
29.2, 30.6, 32.7, 57.2, 59.3, 89.8, 113.1, 120.7, 122, 129.6,
130.2, 133.2, 151.6, 153.1, 158.5, 159.8, 161.9 ppm; MS: m/z
¼ 340 (M+).
This journal is © The Royal Society of Chemistry 2015
RSC Adv., 2015, 5, 13643–13647 | 13647