Transfer Reagents 4: Retro-Diels–Alder Routes to 3,6-Di(2-pyridyl)pyridazinonorbornadiene, a Test Bed for the Relative Dienofugacity of Isobenzofuran, Isoindole, and Anthracene
作者:Davor Margetić、Douglas Butler、Ronald Warrener
DOI:10.1055/s-0033-1339879
日期:——
reacted with 3,6-di(2-pyridyl)-s-tetrazine to produce pyridazines (diene-protected alkenes), following dehydrogenation (by DDQ) of the intermediate dihydropyridazines. The title 3,6-di(2-pyridyl)-pyridazinonorbornadiene was produced under flash vacuum pyrolysis conditions by ejection of anthracene (590 °C), isobenzofuran (630 °C) or isoindole (580 °C) from the corresponding pyridazines, establishing
Cycloaddition reaction of 2,5‐bis(trifluoromethyl)‐1,3,4‐oxadiazole with strained olefinic bonds of norbornenes was used to synthetize functionalized polynorbornanes. This simple, one step procedure was more effective when reaction was carried out by classical heating, in comparison to microwave‐assisted reactions. Various functional groups were stable in the reaction conditions (ester, imide, phthalimide