782
SHENG-HUI LI et al.
4f: m.p. >300 oC; 1H NMR δ: 2.5 (s, 3H, CH3), 7.8 (s, 2H, NH2), 6.9~8.4 (m, 4H, ArH),
12.0 (s, 1H, NH), 12.7 (s, 1H, NH); IR (KBr) ν: 3401, 3295, 3100, 2219, 1693, 1624, 1191,
1145, 874, 815, 764 cm-1. Anal. calcd for C15H11N5OS: C 58.24, H 3.58, N 22.64, S 10.37;
found C 58.23, H 3.56, N 22.67, S 10.36.
4g: m.p. >300 oC; 1H NMR δ: 8.1 (s, 2H, NH2), 6.5~8.1 (m, 3H, ArH), 11.5 (s, 1H, NH),
12.4 (s, 1H, NH); IR (KBr) ν: 3409, 3327, 3223, 2168, 1733, 1690, 1129, 1029, 883, 775,
711 cm-1. Anal. calcd for C14H7Cl2N6O5S: C 46.17, H 1.94, N 19.23, S 8.80; found C 46.19,
H 1.92, N 19.22, S 8.81.
4h: m.p. >300 oC; 1H NMR δ: 3.8 (s, 3H, CH3), 7.6 (s, 2H, NH2), 6.7~7.9 (m, 3H, ArH),
11.8 (s, 1H, NH), 12.0 (s, 1H, NH); IR (KBr) ν: 3454, 3380, 3299, 2217, 1691, 1628, 1240,
1032, 877, 834, 804, 722 cm-1. Anal. calcd for C15H11N5O2S: C 55.38, H 3.41, N 21.53,
S 9.86; found C 55.37, H 3.39, N 21.52, S 9.88.
o
1
4i: m.p. >300 C; H NMR δ: 7.7 (s, 2H, NH2), 7.3 (d, 2H,J=8.0, ArH), 7.4 (d, 2H,
J=8.0, ArH), 12.0 (s, 1H, NH), 12.7 (s, 1H, NH); IR (KBr) ν: 3455, 3296, 3217, 2215, 1694,
1622, 1269, 1089, 1014, 934, 875, 805, 764, 725 cm-1. Anal. calcd for C14H8ClN5OS: C
50.99, H 2.45, N 21.24, S 9.72; found C 50.97, H 2.48, N 21.23, S 9.72.
o
1
4j: m.p.>300 C; H NMR δ: 7.4 (s, 2H, NH2), 6.4~7.7 (m, 3H, ArH), 12.1 (s, 1H, NH),
12.7 (s, 1H, NH); IR (KBr) ν: 3404, 3309, 3223, 2172, 1694, 1625, 1267, 1141, 1075, 873,
803, 699 cm-1. Anal. calcd for C14H8ClN5OS: C 50.99, H 2.45, N 21.24, S 9.72; found C
50.97, H 2.44, N 21.22, S 9.72.
Results and Discussion
In presence of SDS, aromatic aldehyde 1, malononitrile 2 and 6-amino-4-hydroxy-2-
o
mercaptopyrimidine 3 were performed in water at 90 C, 7-amino-5-argio-4-oxo-2-thioxo-
1,2,3,4-tetrahydropyrido[2,3-d]pyrimidine-6-carbonitrile 4 were obtained in moderate to
good yield. The results are summarized Table 1.
Initially, we investigated the catalytic activity of various phase-transfer catalysis (PTC)
or surfactant such as hexadecyltrimethylammonium bromide (HTMAB), benzyltrimethyl
ammonium bromide (BTMAB), tetrabutyl ammonium bromide (TBAB), 4-dodecylbenesulfonic
acid (DBSA) and SDS. The results showed that in the presence of SDS, the reaction gives
the corresponding products in good yields (81%).
The catalyst plays a crucial role in this reaction. For example, 4-nitrobenzoaldehyde
reacted with the other materials in the presence of 1 mol% SDS to give the product 4d in low
yield (32%) at reflux in water after 12 h. Increasing the amount of the catalyst to 5 mol%, 10
mol% and 15 mol% results in increasing the reaction yield to 62 %, 81% and 81%.
As shown in Table 1, we can find a series of aromatic aldehyde 1 were reacted with 2
o
and 3 in the presence of SDS in water at 90 C, the reaction proceed smoothly to afford the
corresponding products (4). No obvious effect of the electronic nature of substituents in the
aromatic ring was observed. Benzaldehyde and aromatic aldehydes containing electron-
donating groups (such as alkyl group, alkoxyl group) or electron withdrawing groups (such
as halide, nitro group) were employed and reacted to give the corresponding products 4 in
moderate to good yield under this reaction conditions.
The structure of the compound was ascertained from spectroscopic data and elemental
analysis. Take (4d) as the example, sharp bands at 3215 cm-1 (NH2) and 2215 cm-1 (CN)
were observed in the IR spectrum of the compound. The 1H NMR spectra showed the