Results Cyclodeca-1, 2, 5, 8-tetraene (3) was prepared from cyclonona-l, 4, 7-trienel0 by the method which involves addition of a dibromo carbenoid and subsequent conversion to the allene using methyllithium. 8 Cyclodeca-172, 5-triene (7) was prepared in a similar way from 1, 4-cyclononadiene. l1
