L-TyrosineasanEco-FriendlyandEfficientCatalystfor.PDFVIP

Hindawi Publishing Corporation Organic Chemistry International Volume 2012, Article ID 191584, 4 pages doi:10.1155/2012/191584 Research Article L-Tyrosine as an Eco-Friendly and Efficient Catalyst for Knoevenagel Condensation of Arylaldehydes with Meldrum’s Acid in Solvent-Free Condition under Grindstone Method G. Thirupathi, M. Venkatanarayana, P. K. Dubey, and Y. Bharathi Kumari Department of Chemistry, College of Engineering, Jawaharlal Nehru Technological University Hyderabad, Kukatpally, Hyderabad 500085, India Correspondence should be addressed to G. Thirupathi, thirupathigjntuh@ Received 8 September 2012; Revised 18 October 2012; Accepted 20 October 2012 Academic Editor: Ashraf Aly Shehata Copyright © 2012 G. Thirupathi et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. We investigate L-Tyrosine as an efficient catalyst for the Knoevenagel condensation of arylaldehydes with meldrum’s acid contain- ing cyclic active methylene group in solvent-free condition under grindstone method at room temperature to produce substituted- 5-benzylidene-2,2-dimethyl-[1,3]dioxane-4,6-diones 3(a–j). 1. Introduction that assisted Knoevenagel condensation in organic syn- thesis. Toda introduced a method called the grindstone method Knoevenagel condensation of meldrum’s acid and alde- [1, 2]. In this method, solids are grounded together using a hydes gives rise to substrates for variety of reactions [28]. pestle and mortar to get the products. These reactions are They