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HETEROCYCLES, Vol. 68, No. 3, 2006
129.5, 129.8, 130.2 (5 x Ar CH), 63.2, 130.2, 134.4, 135.2, 173.7, 175.3, 202.3 (7 x qC). Anal. Calcd for
C19H16NO3Cl: C, 66.76; H, 4.68; N, 4.10. Found: C, 66.65, H, 4.63, N, 4.0.
ESMS (MeCN CV +36 V)
m/z 364 ([M + Na+]+, 100%).
Synthesis of 3-Acetyl-3-methyl-1-(4-chlorophenyl)pyrolidin-2,5-dione (3D)
The oil purified by column chromatography using SiO2 and a mixture of EtOAc and hexane as eluant
(50%:50% by volume) to give the product as the faster eluting component as a white solid (300 mg, 20%)
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mp 102-1050C (EtOH). IR (KBr) 2986, 1706, 1495, 1397, 1200, 1091, 875 cm-1. H NMR (CDCl3): δ
1.73 (3H, s, CH3), 2.40 (3H, s, CH3), 2.53 (1H, d, CH2, J = 18.4), 3.60 (1H, d, CH2, J = 18.4), 7.20 (2H,
m, 2 x Ar CH), 7.43 (2H, m, 2 x Ar CH). 13C NMR (CDCl3): δ 22.3 (CH3), 26.5 (CH3), 38.7 (CH2), 57.9,
130.4, 135.0, 174.0, 176.0, 203.0 (6 x qC), 128.0, 130.0 (2 x Ar CH). Anal. Calcd for C13H12NO3Cl: C,
58.75; H, 4.52; N, 5.27. Found: C, 58.60; H, 4.50; N, 5.15 ESMS (MeOH CV +20 V) m/z 274 ([M +
Na+]+, 100%).
Synthesis of 3-Acetyl-3-ethyl-1-(phenyl)pyrolidine-2,5-dione (3E)
White solid (800 mg, 19%) mp 82-850C (EtOH). IR (KBr) 2984, 1707, 1488, 1395, 1187, 1103, 971,
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864 cm-1. H NMR (CDCl3): δ 1.00 (3H, t, CH3, J = 7.2), 2.20 (2H, m, CH2), 2.50 (3H, s, CH3, J = 6.8),
2.60 (1H, d, CH2, J = 18.8), 3.70 (1H, d, CH2, J = 18.8), 7.20 (2H, m, 2 x Ar CH), 7.40-7.45 (3H, m, 3 x
Ar CH). 13C NMR (CDCl3): δ 9.30, 26.5 (2 x CH3), 29.0, 35.0 (2 x CH2), 63.2, 132.0, 174.5, 175.7, 203.0
(5 x qC), 126.8,129.2, 129.6 (3 x Ar CH) ). Anal. Calcd for C11H15NO3: C, 68.57; H, 6.12; N, 5.71,
Found: C, 68.56; H, 6.17; N, 5.71. ESMS (MeCN CV +30 V) m/z 268 ([M + Na+]+, 100%).
Synthesis of α-Ethoxycarbonylmethyl-4-chloroacetoacetanilide (5B) Y = Cl
Procedure as for 5A21. White solid (2g, 40%), mp 90-920C. (EtOH). IR (KBr) 3306, 2987, 1708, 1602,
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1539, 1400, 1338, 1202, 1089, 833 cm-1. H NMR (CDCl3): δ 1.27 (3H, m, CH3, J = 7.4), 2.30 (3H, s,
CH3), 3.00 (2H, m, CH2, J = 8.0), 3.90 (1H, t, CH, J = 6.8), 4.15 (2H, q, CH2, J = 7.2), 7.25 (2H, d, 2 x Ar
CH, J = 7.0), 7.44 (2H, d, 2 x Ar CH, J = 6.8), 8.71 (1H, s, NH). 13C NMR (DMSO-d6): δ 14.5, 29.3, (2 x
CH3), 33.5, 62,0 (2 x CH2), 57.7 (CH), 121.6, 129.4 (2 x Ar CH), 130.2, 136.5, 166.0, 172.5, 204.8 (5 x
qC).
Anal. Calcd for C14H16NO4Cl: C, 56.47; H, 5.38; N, 4.70, Found: C, 56.50; H, 5.25; N, 4.61.
ESMS (MeCN CV +30 V) m/z 320 ([M + Na+]+, 100%).
Synthesis of 3-Acetyl-3-ethyl-5-imino-1-phenyl-pyrrolidin-2-one (7)
3-Ethylacetoacetanilide (6) (3.5 g, 17 mmol) was heated under reflux in acetone (150 mL) with NaH
(60% dispersion, 1g, 25 mmol) and chloroacetonitrile (1.6 mL, 25 mmol) for 16 h. The reaction was