Efficient synthesis of 4-(2'-alkenyl)-2,5-dihydrofurans and 5,6-dihydro-2H-pyrans via the Pd-catalyzed cyclization coupling reaction of 2,3- or 3,4-allenols with allylic halides

Research has been conducted on the palladium(II) catalysts. The ability of these catalysts to catalyze the coupling reactions of 2,3- and 3,4-allenols with allylic halides in DMA in producing 2,5-dihydrofurans and 5,6-dihydro-2H-pyrans has been investigated and discussed.