1270
D. U. Singh, P. R. Singh, and S. D. Samant
EXPERIMENTAL
General Procedure: Synthesis of 4-(1H-Indol-3-yl)-butan-2-one
A mixture of indole 1a (5 mmol), methyl vinyl ketone 2a (5 mmol), and
K10–FeO (0.5 g) in CH3CN (5 mL) was stirred at room temperature for an
appropriate time (Table 2). After the complete conversion as indicated by
TLC, the catalyst was filtered off. The combined organic layers were concen-
trated in vacuo and purified by column chromatography on silica gel (Merck,
60–120 mesh, EtOAc–pet. ether, 1 : 9) to afford the pure product 3a. Solid;
1
mp 70–718C. IR (KBr): 3400, 2925, 1715, 1355, 1160, 745 cm21. HNMR
(400 MHz, CDCl3): d ¼ 2.15 (s, 3H), 2.80 (t, J ¼ 6.4 Hz, 2H), 3.10
(t, J ¼ 6.4 Hz, 2H), 6.95 (d, J ¼ 2.4 Hz, 1H), 7.15 (t, J ¼ 7.2 Hz, 1H), 7.20
(t, J ¼ 7.2 Hz, 1H), 7.30 (d, J ¼ 7.1 Hz, 1H), 7.60 (d, J ¼ 7.1 Hz, 1H), 8.0
(br, s, 1H, NH). Anal. calcd. for C12H13NO: C, 76.98; H, 7.0; N, 7.48.
Found: C, 77.0; H, 7.03, N, 7.51.
ACKNOWLEDGMENTS
D. U. S. thanks CSIR, New Delhi, India, for the award of fellowships.
REFERENCES
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