1,5-cyclooctadiene 1,3-alkadiene

A hydrocarbon that contains two double bonds is called an alkadiene, and the rela tionship between the double bonds may be described as isolated conjugated or cumu lated Isolated diene units are those m which two carbon-carbon double bond units are separated from each other by one or more sp hybridized carbon atoms 1 4 Pentadiene and 1 5 cyclooctadiene have isolated double bonds... 

Ring-opening cross metathesis. Significant reactions belonging to this category are the formation of the cyclic acetals of l,4-alkadien-2-ones from cyclopropenone acetals and 1-alkenes, and the assemblage of 1,2-dialkenylcyclobutanes en route to complex 1,5-cyclooctadienes. 

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