THE CYCLOADDITION OF ,5,5,5-HEXAFLUORO-3-TRIFLUOROMETHYL-1,3-PENTADIENE WITH PYRIDINE-DERIVATIVES

The reaction of xafluoro-4-phenyl-3-trifluoromethyl-1,3-pentadiene (1) , prepared in several steps from perfluorovinyl bromide (3), and pyrid ine results in the formation of the 4-quinolizone derivatives 6 and 7. The reactions of hexafluoro-4-iodo-3-trifluoromethyl-1,3-pentadiene ( 2), also prepared from perfluorovinyl bromide (3), and pyridine deriva tives result in the formation of the 4-quinolizone derivatives 8-10. S ince the observed cycloaddition reaction would have been expected to p roceed with inverse electron demand, the facile reaction of I and 2 wi th pyridine provides a unique entry to the 4-quinolizone derivatives.