792
L. Fu, G. W. Gribble
PAPER
N-(1-Phenylsulfonyl-1H-pyrrol-3-yl)dimethylmaleimide (7b)
Prepared from 3-nitro-1-phenylsulfonylpyrrole (1b; 0.10 g, 0.40
mmol), tin powder (0.25 g, 2.0 mmol), 2,3-dimethylmaleic anhy-
dride (0.25 g, 2.0 mmol), and AcOH (4 mL) in toluene (6 mL). Col-
umn chromatography with hexanes–EtOAc (4:1) gave 7b (0.11 g,
84%) as a yellow solid. An analytical sample was obtained by sev-
eral recrystallizations from EtOAc; mp 166.5–168 °C.
1H NMR (CDCl3): d = 7.88–7.90 (m, 2 H), 7.66 (dd, J2,4 = 1.7 Hz,
J2,5 = 2.4 Hz, 1 H), 7.59–7.62 (m, 1 H), 7.49–7.53 (m, 2 H), 7.15
(dd, J2,5 = 2.4 Hz, J4,5 = 3.7 Hz, 1 H), 6.87 (dd, J2,4 = 1.7 Hz,
J4,5 = 3.7 Hz, 1 H), 2.01 (s, 6 H).
analytical sample was obtained by several recrystallizations from
EtOAc; mp 161–162 °C.
1H NMR (acetone-d6): d = 8.02 (m, 2 H), 7.77–7.80 (m, 2 H), 7.67
(m, 2 H), 7.34 (dd, J2,5 = 2.6 Hz, J4,5 = 3.4 Hz, 1 H), 6.99 (dd, J2,4
1.5 Hz, J4,5 = 3.4 Hz, 1 H), 2.82 (s, 4 H).
13C NMR (acetone-d6): d = 175.8, 138.9, 134.8, 130.1, 127.2, 123.1,
119.6, 112.8, 109.0, 28.2.
=
Anal. Calcd for C14H12N2O4S: C, 55.26; H, 3.97; N, 9.16; S, 10.59.
Found: C, 55.00; H, 4.16; N, 9.16; S, 10.59.
N-(1-Methyl-1H-pyrrol-2-yl)succinimide (3c)
13C NMR (CDCl3): d = 170.1, 138.9, 138.0, 134.2, 130.0, 127.2,
122.3, 120.0, 111.6, 108.4, 9.1.
Prepared from 1-methyl-2-nitropyrrole (1c; 0.10 g, 0.80 mmol), tin
powder (0.47 g, 4.0 mmol), succinic anhydride (0.40 g, 4.0 mmol),
and AcOH (2 mL) in toluene (6 mL). Column chromatography with
hexanes–EtOAc (1:1) gave 3c (0.13 g, 89%) as a white solid; mp
166–167 °C (Lit.9 mp 163–164 °C).
Anal. Calcd for C16H14N2O4S: C, 58.17; H, 4.27; N, 8.48; S, 9.71.
Found: C, 57.89; H, 4.36; N, 8.49; S, 9.81.
N-(1-Methyl-1H-pyrrol-3-yl)dichloromaleimide (8a)
1H NMR (acetone-d6): d = 6.72 (dd, J3,5 = 1.9 Hz, J4,5 = 3.0 Hz, 1
H), 6.05 (dd, J3,4 = 3.8 Hz, J4,5 = 3.0 Hz, 1 H), 5.93 (dd, J3,4 = 3.8
Hz, J3,5 = 1.9 Hz, 1 H), 3.41 (s, 3 H), 2.89 (s, 4 H).
13C NMR (acetone-d6): d = 176.8, 121.5, 120.6, 106.7, 106.4, 32.4,
28.5.
Prepared from 1-methyl-3-nitropyrrole (1a, 0.10 g, 0.80 mmol), tin
powder (0.47 g, 4.0 mmol), 2,3-dichloromaleic anhydride (0.66 g,
4.0 mmol), and AcOH (4 mL) in toluene (6 mL). Column chroma-
tography with hexanes–EtOAc (4:1) gave 8a (0.15 g, 75%) as a red
solid. An analytical sample was obtained by several recrystalliza-
tions from EtOAc; mp 138.5–139.5 °C.
1H NMR (CDCl3): d = 6.89 (dd, J2,4 = 1.7 Hz, J2,5 = 2.4 Hz, 1 H),
6.58 (dd, J2,5 = 2.4 Hz, J4,5 = 3.0 Hz, 1 H), 6.34 (dd, J2,4 = 1.7 Hz,
J4,5 = 3.0 Hz, 1 H), 3.67 (s, 3 H).
N-(1H-Pyrrol-3-yl)succinimide (3e)
Prepared from 3-nitropyrrole (1e; 0.090 g, 0.80 mmol), tin powder
(0.47 g, 4.0 mmol), succinic anhydride (0.40 g, 4.0 mmol), and
AcOH (3 mL) in toluene (6 mL). Column chromatography with
hexanes–EtOAc (1:1) gave 3e (0.090 g, 68%) as a white solid. An
analytical sample was obtained by several recrystallizations from
EtOAc; mp 150.5–151.5 °C.
1H NMR (CDCl3): d = 8.38 (br s, 1 H), 7.22 (m, 1 H), 6.78 (m, 1 H),
6.60 (m, 1 H), 2.84 (s, 4 H).
13C NMR (CDCl3): d = 176.3, 117.2, 117.1, 112.7, 104.2, 28.4.
13C NMR (CDCl3): d = 162.1, 121.2, 116.4, 115.0, 104.3, 37.0.
Anal. Calcd for C9H6Cl2N2O2: C, 44.11; H, 2.47; Cl, 28.93; N,
11.43. Found: C, 44.18; H, 2.51; Cl, 29.08; N, 11.29.
N-(1-Phenylsulfonyl-1H-pyrrol-3-yl)dichloromaleimide (8b)
Prepared from 3-nitro-1-phenylsulfonylpyrrole (1b; 0.10 g, 0.40
mmol), tin powder (0.25 g, 2.0 mmol), 2,3-dichloromaleic anhy-
dride (0.33 g, 2.0 mmol), and AcOH (4 mL) in toluene (6 mL). Col-
umn chromatography with hexanes–EtOAc (4:1) gave 8b (0.12 g,
80%) as a yellow solid. An analytical sample was obtained by sev-
eral recrystallizations from EtOAc; mp 188–189 °C.
Anal. Calcd for C8H8N2O2: C, 58.53; H, 4.91; N, 17.06. Found: C,
58.55; H, 4.99; N, 16.99.
N-(1H-Pyrrol-2-yl)succinimide (3f)
Prepared from 2-nitropyrrole (1f; 0.090 g, 0.80 mmol), tin powder
(0.47 g, 4.0 mmol), succinic anhydride (0.40 g, 4.0 mmol) and
AcOH (3 mL) in toluene (6 mL). Column chromatography with
hexanes–EtOAc (2:1) gave 3f (0.070 g, 53%) as a white solid. An
analytical sample was obtained by several recrystallizations from
EtOAc; mp 195–196 °C.
1H NMR (CDCl3): d = 7.90 (m, 2 H), 7.62–7.65 (m, 2 H), 7.52–7.55
(m, 2 H), 7.18 (dd, J2,5 = 2.4 Hz, J4,5 = 3.4 Hz, 1 H), 6.79 (dd, J2,4
1.7 Hz, J4,5 = 3.4 Hz, 1 H).
13C NMR (CDCl3): d = 161.1, 138.6, 134.5, 134.0, 129.8, 127.3,
120.9, 120.3, 112.7, 108.3.
=
1H NMR (CDCl3): d = 10.02 (br s, 1 H), 6.70 (m, 1 H), 6.68 (m, 1
H), 6.22 (m, 1 H), 2.87 (s, 4 H).
Anal. Calcd for C14H8Cl2N2O4S: C, 45.30; H, 2.17; Cl, 19.10; N,
7.55; S, 8.64. Found: C, 45.35; H, 2.18; Cl, 19.12; N, 7.43; S, 8.53.
13C NMR (CDCl3): d = 175.0, 123.5, 114.1, 107.8, 99.8, 28.4.
N-(1-Methyl-1H-pyrrol-3-yl)phthalimide (9a)
Anal. Calcd for C8H8N2O2: C, 58.53; H, 4.91; N, 17.06. Found: C,
58.61; H, 4.97; N, 17.13.
Prepared from 1-methyl-3-nitropyrrole (1a; 0.10 g, 0.80 mmol), tin
powder (0.47 g, 4.0 mmol), phthalic anhydride (0.60 g, 4.0 mmol),
and AcOH (4 mL) in toluene (4 mL). Column chromatography with
hexanes–EtOAc (2:1) and recrystallization from EtOAc gave 9a
(0.17 g, 95%) as a yellow solid. An analytical sample was obtained
by several recrystallizations from EtOAc; mp 172.5–174 °C.
1H NMR (CDCl3): d = 7.73–7.91 (m, 4 H), 7.07 (dd, J2,4 = 1.9 Hz,
J2,5 = 2.4 Hz, 1 H), 6.63 (dd, J2,5 = 2.4 Hz, J4,5 = 3.0 Hz, 1 H), 6.53
(dd, J2,4 = 1.9 Hz, J4,5 = 3.0 Hz, 1 H), 3.71 (s, 3 H).
N-(1-Methyl-1H-pyrrol-3-yl)dimethylmaleimide (7a)
Prepared from 1-methyl-3-nitropyrrole (1a; 0.10 g, 0.80 mmol), tin
powder (0.47 g, 4.0 mmol), 2,3-dimethylmaleic anhydride (0.50 g,
4.0 mmol), and AcOH (4 mL) in toluene (6 mL). Column chroma-
tography with hexanes–EtOAc (4:1) gave 7a (0.13 g, 77%) as an or-
ange solid. An analytical sample was obtained by several
recrystallizations from EtOAc; mp 120.5–122 °C.
13C NMR (CDCl3): d = 167.5, 134.3, 132.3, 123.6, 121.0, 116.4,
116.3, 104.5, 37.0.
1H NMR (CDCl3): d = 6.88 (m, 1 H), 6.55 (m, 1 H), 6.35 (m, 1 H),
3.65 (s, 3 H), 2.01 (s, 6 H).
Anal. Calcd for C13H10N2O2: C, 69.02; H, 4.46; N, 12.38. Found: C,
68.80; H, 4.40; N, 12.33.
13C NMR (CDCl3): d = 171.3, 137.4, 120.8, 116.4, 115.7, 104.1,
36.9, 9.1.
Anal. Calcd for C11H12N2O2: C, 64.69; H, 5.92; N, 13.72. Found: C,
64.80; H, 6.05; N, 13.65.
N-(1-Phenylsulfonyl-1H-pyrrol-3-yl)phthalimide (9b)
Prepared from 3-nitro-1-(phenylsulfonyl)pyrrole (1b; 0.10 g, 0.40
mmol), tin powder (0.25 g, 2.0 mmol), phthalic anhydride (0.30 g,
Synthesis 2008, No. 5, 788–794 © Thieme Stuttgart · New York