Coumarin syntheses via Pechmann condensation in Lewis acidic chloroaluminate ionic liquid
Mahesh K. Potdar, Swapnil S. Mohile and Manikrao M. Salunkhe*
*Department of Chemistry, The Institute of Science, 15 Madam Cama Road, Mumbai 400 032, India, Email: mmsalunkhehotmail.com
M. K. Potdar, S. S. Mohile, M. M. Salunkhe, Tetrahedron Lett., 2001, 42, 9285-9287.
The ionic liquid 1-butyl-3-methylimidazolium chloroaluminate ([bmim]Cl•2AlCl3) plays the dual role of solvent and Lewis acid catalyst in the Pechmann condensation of phenols with ethyl acetoacetate leading to coumarin derivatives. The reaction time is reduced drastically even at ambient conditions.
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