51544-87-7Relevant academic research and scientific papers
Another aspect of the reaction behavior of cyclopentadienones: 1,5-Sigmatropic rearrangement of the 1,4-addition products of amines
Yamaguchi, Koki,Kai, Chika,Yoshitake, Yasuyuki,Harano, Kazunobu
, p. 826 - 834 (2004)
Treatment of 2,5-bis(methoxycarbonyl)-3,4-diphenylcyclopentadienone (1) with aniline (2a) gave the stereoisomeric 2-anilino-2,5-bis(methoxycarbonyl)-3, 4-diphenylcyclopentenones (cis- and trans-4a). 1H NMR spectroscopic monitoring of the reaction indicates that both compounds are derived from the 1,5-sigmatropic rearrangement of the 1,4-addition products cis- and trans-3a. The structure of 3a was established by the X-ray analysis of the product after methylation (3a-Enol-Me) with diazomethane. The sequential pericyclic reaction behavior of 1 with amines is discussed on the basis of X-ray crystal structures and the optimized structure of the transition state at the B3LYP/6-31G(d) level of theory. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004.
