A. K. Sinha, A. Sharma and B. P. Joshi, “One-Pot Two-Step Synthesis of 4-Vinylphenols from 4-Hydroxy Substituted Benzaldehydes under Microwave Irradiation: A New Perspective on the Classical Knoevenagel-Doeb- ner Reaction,” Tetrahedron, Vol. 63, No. 4, 2007, pp. 960- 965. doi:10.1016/j.tet.2006.11.023

has been cited by the following article:

• TITLE: Organocatalyzed Decarboxylation of Naturally Occurring Cinnamic Acids: Potential Role in Flavoring Chemicals Production

  AUTHORS: Virginia Aldabalde, María Lucía Derrudi, Daniela Gamenara, Federico Geymonat, Patricia Saenz-Méndez, Mariela Risso, Gustavo Seoane

  KEYWORDS: β-Unsaturated Carboxylic Acids, Decarboxylation, Vinylphenols, Organocatalysis, Knoevenagel

  JOURNAL NAME: Open Journal of Physical Chemistry, Vol.1 No.3, November 25, 2011

  ABSTRACT: The mechanism and the final outcome of the Knoevenagel-Doebner reaction are discussed. The condensation reaction between different hydroxy-substituted aromatic aldehydes and malonic acid is performed using piperidine as organocatalyst. The key role of the catalyst is clearly pointed out during the decarboxylation of ferulic acid, without the use of a strong decarboxylating agent, leading to a 4-vinylphenol derivative. Based on the results obtained, the studied pathway may be important in the understanding of vinylphenol production during malting and brewing of wheat and barley grains. Finally, changing the solvent of the reaction from pyridine to water in the Knoevenagel-Doebner reaction of 4-hydroxybenzaldehydes, dimerization of resulting styrene derivatives is observed. These results can be of interest also in the field of food chemistry, since cinnamic acids are frequently found in fruits and vegetables used for human consumption.