PYROLYTIC REARRANGEMENT OF 2 CYCLOBUTENE EPOXIDES

The pyrolytic rearrangement of exo-bicyclo[3.2.0]hept-6-ene oxide (1) and exo-bicyclo[4.2.0]oct-7-ene oxide (6) have been investigated. At 420°, the former gives ∆2-cyclopentenylacetaldehyde (2) in 50% yield. At 400°, the latter gives ∆2-cyclohexenylacetaldehyde (7), 1-methylcyclohexene, and 3.4-tetramethylene-2,3-dihydrofuran (8). The corresponding cyclobutanones (10 and 11) were shown not to be intermediates. The structures of the products have been assigned on the basis of comparison with authentic samples and further chemical transformations. © 1969, American Chemical Society. All rights reserved.