Thermolysis of cyclobutenones

Bridged cycloocta enes result from Cope rearrangement of fused substrates, following the theme seen in Scheme 12. A general route to the requisite substrates is the [2 2] cycloaddition of vinylketenes to cyclic 1,3-dienes, illustrated in equations (61) and (62) the vinylketenes may be formed by dehydroha-logenation of unsaturated acid chlorides or by thermolysis of cyclobutenones. ... 

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