82390-65-6Relevant academic research and scientific papers
Cycloadditions, 6 Intramolecular Diels-Alder Reaction of Allenecarboxanilides; Variation of the Residue Geminal to the Carboxamide Group
Henn, Lothar,Himbert, Gerhard,Diehl, Klaus,Kaftory, Menahem
, p. 1953 - 1963 (2007/10/02)
The 2,3-butadienanilides 6a-h, unsubstituted in the ω-position, are synthesized by the ynamine way and submitted to thermolysis.They isomerize without exception by intramolecular Diels-Alder reaction more or less quickly, irreversibly, and quantitatively
Cycloadditions, 9: Intramolecular Diels-Alder Reaction of Allenecarboxanilides; Incorporation of the Amide Nitrogen Atom in Benzo- and Dibenzo-condensated Five-, Six-, and Seven-membered Rings
Diehl, Klaus,Himbert, Gerhard
, p. 2874 - 2888 (2007/10/02)
The allenecarboxanilides 6a-f, the amide nitrogen atom of which is part of a benzo-condensated five-, six-, or seven-membered ring, are synthesized via phosphorus ylides.Thermolysis of 6 in refluxing xylene induces the intramolecular Diels-Alder reaction only in those cases, where the heterocycle is six- or seven-membered.The allenecarboxamide 6b with the six-membered ring bearing only one benzene nucleus in addition furnishes the quinoline derivatives 9 and 10 as main products, while in the case of the allenecarboxamides 6a,c possessing a five-membered heterocycle no reaction takes place whatever.It is tried to explain this different thermolytic behaviour by taking into consideration the spatial arrangement of the two reacting ?-systems (allene and arene) determined by the structure.
