Susana M. M. Lopes, M. Henriques, J. A. Paixão
Oct 1, 2015
Citations
0
Influential Citations
24
Citations
Journal
European Journal of Organic Chemistry
Abstract
The reactivity of 2,2-bis(furan-2-yl)propane towards nitroso- and azoalkenes was explored. The expected hetero-Diels–Alder adducts, 4a,7a-dihydro-4H-furo[2,3-e][1,2]oxazines and 4a,7a-dihydrofuro[3,2-c]pyridazines, were obtained in good yield. The furo-oxazines were easily converted into the corresponding bis(furan-2-yl)methanes bearing an open-chain oxime. Interestingly, the synthesized furo-pyridazines showed a different chemical behavior. In the presence of HCl, they underwent a rearrangement giving 6-(2-oxobutyl)-1,6-dihydropyridazine derivatives in a process having as its key step a furan ring-opening reaction. The synthesis of 4a,7a-dihydrofuro[3,2-c]pyridazines from 2-methylfuran and the subsequent acid-catalysed rearrangement to the corresponding 6-(2-oxopropyl)-1,6-dihydropyridazines was also achieved.