The product 3 was previously prepared [1] using C6H6 in the presence of pyridine. A mixture of hydroquinone 1 (0.66 g, 6 mmol), ethyl acetoacetate 2 (0.78 g, 6 mmol) and monmorillonite K10 (0.43 g, 30 % by weight of the total reactants) [2,3] was placed in a pyrex tube which was then introduced into a Maxidigest MX 350 Prolabo microwave monomode reactor fitted with a rotational system [4]. An approximate final temperature (120 °C) was measured by introducing a digital thermometer at the end of the irradiation time (20 min on 180 W as irradiation power). The mixture was cooled to ambient temperature. After elution with ethyl acetate (30 mL) and subsequent filtration through florisil, the organic product was purified by chromatography on silicagel (dichloromethane : ethyl acetate, 90 :10), yield : 65 % of 3 white solid.
Melting point: 96-98 °C.
1H NMR d (CDCl3, 200 MHz): 7-6.7 (2d, 4H, Ph); 5,65 (s, OH) ; 3.7 (s, CH2); 2.38 (s, CH3).
13C NMR d (CDCl3, 100 MHz): 30 (CH3); 50 (CH2); 116 and 123 (C=C arom.); 155 (CO2); 202 (C=O acyl).
MS (IC-NH3, m / z): 212(M+ + 18) / 100 %.
Supplementary materials
Supplementary File 1Supplementary File 2Supplementary File 3References
- Rall, K.B.; Perekalin, V.V. Zhurnal Obshchei Khimii 1955, 25, 259.
- Li, T.S.; Zhang, Z.H.; Yang, F.; Fu, C.G. J. Chem. Research (S) 1998, 38–39.
- Singh, J.; Kaur, J.; Nayyar, S.; Kad, G.L. J. Chem. Research (S) 1998, 280–281.
- Kappe, C.O.; Dallinger, D. Nature Reviews Drug Discovery 2006, 5, 51. [PubMed]; De la Hoz, A.; Diaz-Ortiz, A.; Moreno, A. Chem. Soc. Rev. 2005, 34, 164. [PubMed]
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