4
52
K. Panda et al.
LETTER
(
13) For our recent quinoline synthesis see: Mahata, P. K.;
Venkatesh, C.; Syam Kumar, U. K.; Ila, H.; Junjappa, H.
J. Org. Chem. 2003, 68, 3966.
crude iminoenamines which were used as such for further
reactions whereas few of the iminoenamines were purified
by column chromatography over silica gel using hexane–
EtOAc (9:1) as eluent for characterization. The crude
iminoenamine (5 mmol) obtained was dissolved in PPA (20
mL) and the reaction mixture was heated with stirring at
90 °C for 6 h (monitored by TLC). It was then cooled,
poured into ice-cold H O (50 mL), extracted with CHCl
(14) All new compounds gave satisfactory spectral and analytical
data.
(
15) General Procedure for the Synthesis of Substituted and
Fused Quinolines 3a–e, 6, 8, 10: Method A: A solution of
3-bis(methylthio)acrolein (1, 2.0 mmol, 0.3 g) and the
2
3
appropriate anilines (2.2 mmol) or aryldiamines (1.1 mmol)
in glacial HOAc (30 mL) was heated under reflux for 8–10
h (monitored by TLC). It was then cooled, quenched with
sat. NaHCO solution, extracted with CHCl (3 × 30 mL),
(3 × 50 mL), the combined organic layer was washed with
H O (3 × 50 mL) and dried over Na SO .The solvent was
2
2
4
distilled off to give crude product, which was purified by
column chromatography over silica gel using hexane–
EtOAc (9:1) as eluent.
3
3
the combined organic layer was washed with H O (50 mL)
2
and dried over Na SO . Removal of solvent gave crude
Data for compound 3m: Yield 60%; yellow liquid; R = 0.8
2
4
f
products, which were purified by column chromatography
over silica gel using hexane–EtOAc (9:1) as eluent. Data for
compound 3a: Yield 78%; light yellow solid; mp 43–44 °C;
(hexane–EtOAc, 8:2). IR (KBr): 2928, 2359, 1723, 1618
–
1 1
cm . H NMR (400 MHz, CDCl ): d = 2.66 (s, 3 H, SMe),
3
3.96 (s, 3 H, OMe), 6.93 (dd, J = 1.4, 8.0 Hz, 1 H, ArH),
R = 0.4 (hexane–EtOAc, 9:1). IR (KBr): 2999, 2924, 1593
7.15–7.26 (m, 3 H, ArH), 7.76 (d, J = 8.8 Hz, 1 H, ArH). 13C
f
–
1 1
cm . H NMR (400 MHz, CDCl ): d = 2.69 (s, 3 H, SMe),
NMR (100 MHz, CDCl ): d = 12.91, 56.12, 108.80, 119.57,
3
3
3
(
7
.94 (s, 3 H, OMe), 7.07 (dd, J = 2.4, 8.8 Hz, 1 H, ArH), 7.10
d, J = 8.5 Hz, 1 H, ArH), 7.30 (d, J = 2.4 Hz, 1 H, ArH),
.58 (d, J = 8.8 Hz, 1 H, ArH), 7.80 (d, J = 8.5 Hz, 1 H,
120.90, 125.15, 126.82, 135.26, 139.94, 154.19, 159.04. MS
+
(EI): m/z (%) = 206 (100) [M + 1], 191 (20). Anal. Calcd for
C H NOS (205.28): C, 64.36; H, 5.40; N, 6.82%. Found:
1
1
11
1
3
ArH). C NMR (100 MHz, CDCl ): d = 12.98, 55.45,
C, 64.58; H, 5.32; N, 6.60%.
3
106.62, 117.74, 118.15, 120.73, 128.58, 134.89, 149.96,
(18) Zirnstein, M. A.; Staab, H. A. Angew. Chem., Int. Ed. Engl.
1987, 26, 460.
+
160.17, 160.88. MS (EI): m/z (%) = 205 (100) [M ], 159
(
42.8). Anal. Calcd for C H NOS (205.28): C, 64.36; H,
(19) Data for compound 12: Yield 60%; yellow solid; mp 78 °C;
1
1
11
5
.40; N, 6.82%. Found: C, 64.30; H, 5.45; N, 6.75%.
R = 0.7 (hexane–EtOAc, 8:2). IR (KBr): 3371, 2925, 1628,
f
–
1 1
Data for compound 6: Yield 67%; white solid; mp 125–
1597 cm . H NMR (400 MHz, CDCl ): d = 2.51 (s, 6 H,
3
1
1
3
26 °C; R = 0.7 (hexane–EtOAc, 9:1). IR (KBr): 2919,
611, 1593 cm . H NMR (400 MHz, CDCl ): d = 2.77 (s,
2 × SMe), 7.25 (d, J = 8.3 Hz, 2 H, ArH), 7.52 (s, 2 H, ArH),
f
–
1
1
13
7.70 (d, J = 8.3 Hz, 2 H, ArH). C NMR (100 MHz, CDCl ):
3
3
H, SMe), 2.80 (s, 3 H, SMe), 7.36 (d, J = 8.5 Hz, 1 H,
d = 21.71, 126.21, 127.20, 127.38, 129.90, 133.87, 135.40.
+
ArH), 7.44 (d, J = 8.5 Hz, 1 H, ArH), 7.83 (d, J = 9.0 Hz, 1
H, ArH), 7.93 (d, J = 8.2 Hz, 2 H, ArH), 9.25 (d, J = 8.5 Hz,
MS (EI): m/z (%) = 273 (70) [M + 1], 225 (30). Anal. Calcd
for C H N S (272.40): C, 61.73; H, 4.44; N, 10.28%.
1
4
12
2 2
1
1
1
2
H, ArH). 13C NMR (100 MHz, CDCl ): d = 13.17, 13.31,
Found: C, 61.58; H, 4.32; N, 10.40%.
3
20.42, 120.93, 122.47, 123.06, 125.77, 129.32, 132.43,
35.24, 145.41, 148.99, 159.80, 161.44. MS (EI): m/z (%) =
73 (100) [M + 1], 258 (10). Anal. Calcd for C H N S
(20) Data for compound 15a: Yield 88%; white solid; mp 160–
161 °C; R = 0.5 (hexane–EtOAc, 8:2). IR (KBr): 3015,
f
+
–1 1
2927, 1620, 1302 cm . H NMR (400 MHz, CDCl ): d =
3.26 (s, 3 H, OMe), 3.89 (s, 3 H, SO Me), 7.26 (dd, J = 2.7,
1
4
12
2
2
3
(
4
272.40): C, 61.73; H, 4.44; N, 10.28%. Found: C, 61.50; H,
.35; N, 10.42%.
Data for compound 8: Yield 65%; white solid; mp 225–
2
9.0 Hz, 1 H, ArH), 7.40 (d, J = 2.7 Hz, 1 H, ArH), 7.71 (d,
J = 9.0 Hz, 1 H, ArH), 7.89 (d, J = 8.3 Hz, 1 H, ArH), 8.24
1
3
2
3
2
26 °C; R = 0.7 (hexane–EtOAc, 9:1). IR (KBr): 3748,
621, 2924, 1579 cm . H NMR (400 MHz, CDCl ): d =
.86 (s, 6 H, 2 × SMe), 7.41 (d, J = 8.6 Hz, 2 H, ArH), 7.87
(d, J = 8.3 Hz, 1 H, ArH). C NMR (100 MHz, CDCl ): d =
f
3
–
1 1
39.99, 55.68, 107.38, 114.16, 122.89, 124.68, 128.72,
3
138.25, 149.02, 157.51, 161.93. MS (EI): m/z (%) = 238
+
(
d, J = 8.8 Hz, 2 H, ArH), 8.03 (d, J = 8.6 Hz, 2 H, ArH),
(100) [M + 1], 206 (30). Anal. Calcd for C H NO S
1
1
11
3
1
3
9.25 (d, J = 8.8 Hz, 2 H, ArH). C NMR (100 MHz, CDCl ):
(237.28): C, 55.68; H, 4.67; N, 5.90%. Found: C, 55.60 H,
4.75; N, 5.85%.
3
d = 13.26, 121.25, 121.77, 124.56, 125.66, 131.18, 135.49,
+
145.45, 158.96. MS (EI): m/z (%) = 323 (40) [M + 1], 273
(21) Data for compound 17: Yield 80%; white low melting point
(
4
10). Anal. Calcd for C H N S (322.46): C, 67.05; H,
.38; N, 8.69%. Found: C, 67.10; H, 4.25; N, 8.42%.
solid; R = 0.6 (hexane–EtOAc, 8:2). IR (KBr): 3232, 2998,
1
8
14
2
2
f
–
1 1
2930, 1613 cm . H NMR (400 MHz, CDCl ): d = 3.88 (s,
3
(
16) Kar, G. K.; Karmakar, A. C.; Makur, A.; Ray, J. K.
Heterocycles 1995, 41, 911.
3 H, OMe), 4.69 (d, J = 5.1 Hz, 2 H, CH ), 5.16 (br s, 1 H,
2
NH), 6.47 (d, J = 8.6 Hz, 1 H, ArH), 6.86 (dd, J = 2.4, 8.6
Hz, 1 H, ArH), 7.08 (d, J = 2.4 Hz, 1 H, ArH), 7.27 (t, J = 7.0
Hz, 1 H, ArH), 7.33 (t, J = 7.0 Hz, 2 H, ArH), 7.39 (d, J = 7.0
Hz, 2 H, ArH), 7.45 (d, J = 8.8 Hz, 1 H, ArH), 7.72 (d,
(
17) General Procedure for the Synthesis of Substituted and
Fused Quinolines 3f–m, 12: Method B: To a solution of 3-
bis(methylthio)acrolein (1, 2.0 mmol, 0.3 g) and respective
anilines 2f–m (4.4 mmol) or o-phenylenediamine (11, 3.0
mmol) in CH Cl (20 mL), TFA (6.0 mmol, 0.46 mL) was
1
3
J = 8.8 Hz, 1 H, ArH). C NMR (100 MHz, CDCl ): d =
3
45.89, 55.33, 105.40, 108.35, 114.23, 118.22, 127.28,
127.63, 128.44, 128.63, 137.21, 139.21, 149.48, 157.20,
2
2
added at r.t. and the reaction mixture was left for stirring at
the same temperature for 5–6 h (monitored by TLC). It was
+
161.10. MS (EI): m/z (%) = 265 (100) [M + 1]. Anal. Calcd
then quenched with sat. NaHCO solution (2 × 25 mL),
for C H N O (264.33): C, 77.25; H, 6.10; N, 10.60%.
Found: C, 77.15; H, 6.20; N, 10.65%.
3
17 16
2
extracted with CH Cl (2 × 25 mL), dried over Na SO .The
2
2
2
4
organic layer was distilled off under reduced pressure to give
Synlett 2004, No. 3, 449–452 © Thieme Stuttgart · New York