111998-22-2Relevant academic research and scientific papers
Inter- and Intramolecular hetero Diels-Alder Reactions, XXI - Intramolecular hetero Diels-Alder Reaction of Alkylidene-1,3-dicarbonyl Compounds. Experimental Evidence for an Asymmetric Transition State
Tietze, Lutz F.,Brumby, Thomas,Brand, Siegbert,Bratz, Matthias
, p. 499 - 506 (2007/10/02)
The intramolecular hetero Diels-Alder reaction of heterodienes 13 is described.The heterodienes, which are obtained in situ by Knoevenagel condensation of aldehydes 12a-e with dimethylbarbituric acid (2), yield the cycloadducts 14a-e/15a-e and the ene adducts 16a, c-e/17a, c-e.The ratio of 14/15 was determined by HPLC.The resulting data are interpreted as experimental evidence of an asymmetrical transition state of the Diels-Alder reaction.
