SnCl2·2H2O - An alternative to Lewis acidic ionic liquids

Chemistry Letters

Volumn 35, Issue 6, 2006, Pages 632-633

  Arumugam, Pandurangan ^a   Perumal, Paramasivan T ^a  

^a CENTRAL LEATHER RESEARCH INSTITUTE   (India)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 33748098677     PISSN: 03667022     EISSN: None     Source Type: Journal    
DOI: 10.1246/cl.2006.632     Document Type: Article

References (15)

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14. 2O became a viscous liquid. To this viscous liquid was added 1 g (6.5 mmol) of vanillin followed by 1.53 g (13.2 mmol) of indole and stirred at 40 °C. The whole reaction mixture became uniform cherry red colour viscous mass. TLC monitored after 2 min showed that both the starting materials disappeared. To this viscous mass was added small amount of ethanol, stirred, and added 40 mL of ice-cold water and stirred for few min. The solid obtained was filtered under suction and the crude product was dissolved in ethyl acetate, filtered to remove the insoluble stannous salt associated with the reaction mixture. The organic layer thus obtained was dried over anhydrous sodium sulphate, filtered and evaporated the solvent under reduced pressure. The crude product was purified by silica gel (60-120 mesh) column chromatography using petroleum ether (bp 60-80 °C)/EtOAc (9/1) mixture as eluent to obtain 2.25 g (93%) of bis(indolyl)methane.
15. 2O was again utilized for recycling the reaction medium (successfully recycled 7 times). The yield did not vary much while recycling the reaction medium, thus the yield of seven runs were 93, 93, 91, 90, 88, 88, and 85, respectively.