Synthesis of 4-aryl-4,5-dihydro-1H-indeno[1,2-d]pyrimidines by Biginelli
445
219, 114, 77, 59; Anal.Calcd for C17H 14N2S: C 73.38, C6CH2), 1.24–1.26 (s, 3H, S-CH3); m/z 336 M+, 335,
H 5.03, N 10.07. Found: C 73.05, H 4.98, N 10.09%
321, 320, 263; Anal.Calcd for C19H16N2SO2: C 67.86,
H 4.76, N 8.33. Found: C 67.43, H 4.52, N 8.21%
3b H NMR (δ,ppm): 6.87–7.62 (m, 8H, NH & Ar-H),
1
2.1j 4-[4-(Dimethylamino)phenyl]-1,3,4,5-tetrahydro
-2H-indeno[1,2-d]pyrimidine-2-thione (10): IR (KBr,
cm−1): 3420.6 (NH), 1190.5 (C=S); 1H NMR (δ,ppm):
9.91 (s, 1H, NH), 8.83 (s, 1H, NH), 7.12–8.25 (m, 8H,
Ar-H), 6.01 (s, 1H,HA); 4.30 (s, 2H, C6CH2), 2.34 (s,
6H, N(CH3)2); Anal.Calcd for C19H19N3S: C 71.02, H
5.92, N 13.08. Found: C 71.10, H 5.98, N 13.07%
6.04 (s, 2H, O-CH2-O), 5.92 (s, 1H,HA), 3.98 (s, 2H,
C6CH2), 3.70–3.75 (q, 1H of S-CH2), 3.11–3.15 (q, 1H
of S-CH2), 1.48–1.51 (t, 3H, S-CH2-CH3); Anal.Calcd
for C20H18N2SO2: C 68.57, H 5.14, N 8.00. Found: C
68.45, H 5.28, N 7.91%
1
4a H NMR (δ,ppm): 8.18 (s, 1H, NH), 7.02–8.19 (m,
8H, Ar-H & OH), 5.93 (s, 1H,HA), 4.14 (s, 2H, C6CH2),
3.98 (s, 3H, OCH3), 1.90 (s,3H, S-CH3); Anal.Calcd
for C19H18N2SO2: C 67.45, H 5.32, N 8.28. Found: C
67.36, H 5.58, N 8.16%
2.2 General procedure for the synthesis of
2-(Ethyl/methylthio)-4-aryl-4,5-dihydro-1H-
indeno[1,2-d]pyrimidines
1
4b H NMR (δ,ppm): 8.17 (s, 1H, NH), 7.00–8.15 (m,
7H, Ar-H), 8.01(s, 1H, OH), 5.92 (s, 1H,HA), 4.14 (s,
2H, C6CH2), 3.98 (s, 3H, OCH3), 3.69–3.75 (q, 1H, S-
CH2), 3.31–3.35 (q, 1H, S-CH2), 0.85–0.88 (t, 3H, S-
CH2-CH3); Anal.Calcd for C20H20N2SO2: C 68.18, H
5.68, N 7.95. Found: C 68.07, H 5.45, N 7.83%
To indeno[1,2-d]pyrimidine-2-thione 1–10 (0.004
mole) dissolved in ethanol, was added NaOH solution
which was prepared by dissolving NaOH (0.160 g) in
water (2 mL). The mixture was cooled. To this mixture,
diethyl sulphate (0.004 mole) or dimethyl sulphate
(0.004 mole) was added drop-wise while stirring the
reaction mixture continuously. Then the reaction mix-
ture was refluxedfor 3 h. After refluxing, the reaction
mixture was cooled and poured over crushed ice. Solid
separated was filtered under reduced pressure, dried
and recrystallized from ethanol. The spectral data of
the prepared compounds are given below:
1
5a H NMR (δ,ppm): 9.12 (s, 1H, NH), 7.36–8.49 (m,
8H, Ar-H), 6.23 (s, 1H,HA), 4.23 (s, 2H, C6CH2), 2.55
(s, 3H, S-CH3); Anal.Calcd for C18H15N3SO2: C 64.09,
H 4.51, N 12.46. Found: C 63.96, H 4.40, N 12.50%
1
5b H NMR (δ, ppm): 9.05 (s, 1H, NH), 7.36–8.32
(m, 8H, Ar-H), 5.67 (s,1H,HA), 4.13 (s, 2H, C6CH2),
3.56–3.60 (q, 1H, S-CH2), 3.30–3.34 (q, 1H, S-
CH2), 1.46–1.49 (t, 3H, S-CH2-CH3); Anal.Calcd for
C19H17N3SO2: C 64.96, H 4.84, N 11.96. Found: C
64.89, H 4.75, N 11.66%
1
1a H NMR (δ,ppm): 8.13 (s, 1H, NH), 7.02–7.64 (m,
8H, Ar-H), 6.96 (s, 1H,HA), 4.10 (s, 2H, C6CH2), 3.89
(s, 3H, OCH3), 2.72(s,3H, S-CH3); m/z 322 M+, 321,
274, 77; Anal.Calcd for C19H18N2SO: C 70.80, H 5.59,
N 8.69. Found: C 70.72, H 5.28, N 8.60%
1
6a H NMR (δ,ppm): 9.01 (s, 1H, NH), 7.06–8.26 (m,
8H, Ar-H), 5.46 (s, 1H,HA), 4.19 (s, 2H, C6CH2), 2.12
(s, 6H, 4-CH3 & S-CH3); Anal.Calcd for C19H18N2S: C
74.51, H 5.88, N 9.15. Found: C 74.42, H 5.60, N 8.99%
1
1b H NMR (δ,ppm): 8.14 (s, 1H, NH), 6.93–7.59
1
6b H NMR (δ,ppm): 9.11 (s, 1H, NH), 7.10–8.33
(m, 8H, Ar-H), 6.87 (s, 1H,HA), 3.94 (s, 2H, C6CH2),
3.86 (s, 3H, OCH3), 3.70–3.74 (q, 1H of S-CH2),
3.28–3.33 (q, 1H of S-CH2), 1.48–1.51 (t, 3H, S-CH2-
CH3); m/z 336 M+, 335, 275, 249, 219; Anal.Calcd for
C20H20N2SO: C 71.43, H 5.95, N 8.33. Found: C 71.52,
H 5.68, N 8.30%
(m, 8H, Ar-H), 5.57 (s, 1H,HA),4.03 (s, 2H, C6CH2),
3.60–3.64 (q, 1H, S-CH2), 3.43–3.47 (q, 1H, S-CH2),
2.11 (s, 3H, 4- CH3), 1.22–1.25 (t, 3H, S-CH2-CH3);;
Anal.Calcd for C20H20N2S: C 75.00, H 6.25, N 8.75.
Found: C 69.89, H 6.18, N 8.67%
1
1
7a H NMR (δ,ppm): 8.89 (s, 1H, NH), 7.22–7.64 (m,
2a H NMR (δ,ppm): 9.00–9.01 (s, 1H, NH), 7.45–8.55
7H, Ar-H), 6.08 (s, 1H, HA), 4.08 (s, 2H, C6CH2), 1.24
(s, 3H, S-CH3); Anal.Calcd for C18H14N2SCl2: C 59.83,
H 3.88, N 7.75. Found: C 59.72, H 3.52, N 7.60%
(m, 8H, Ar-H), 6.89 (s, 1H,HA); 4.12 (s, 2H, C6CH2),
2.75 (s, 3H, S-CH3); Anal.Calcd for C18H17N3SO2: C
64.09, H 4.51, N 12.46. Found: C 63.99, H 4.58, N
12.52%
1
7b H NMR (δ,ppm): 8.91 (s, 1H, NH), 7.21–7.63 (m,
1
7H, Ar-H), 6.08 (s, 1H,HA), 3.70–3.75 (q, 1H, S-CH2),
3.32–3.36 (q, 1H, S-CH2), 4.11 (s, 2H, C6CH2), 1.22–
1.25 (t, 3H, S-CH2-CH3); Anal.Calcd for C19H16N2S:
C 60.80, H 4.26, N 7.47. Found: C 60.69, H 4.28,
N 7.37%
2b H NMR (δ,ppm): 9.00 (s, 1H, NH), 7.45–8.55 (m,
8H, Ar-H), 5.75 (s, 1H, HA), 4.12 (s, 2H, C6CH2),
3.34–3.38 (q, 2H, S-CH2), 1.50–1.53 (t,3H, S-CH2-
CH3); Anal.Calcd for C19H17N3SO2: C 64.96, H 4.84,
N 11.96. Found: C 64.82, H 4.69, N 11.60%
1
1
9b H NMR (δ,ppm): 8.17 (s, 1H, NH), 7.11–8.15
3a H NMR (δ,ppm): 6.88–7.62 (m, 8H, NH & Ar-H),
(m, 9H, Ar-H), 5.30 (s,1H, HA), 4.13 (s, 2H, C6CH2),
6.04 (s, 2H, O-CH2-O), 5.92 (s, 1H,HA) 3.99 (s, 2H,