Substituent effects in [2σ + 2σ + 2σ] thermal decarbonylation of cage ketones. Remarkably effective elongation of strained C-C bond by through-bond coupling

Article abstract of DOI:10.1021/ja00399a029

Strained pentacyclic ketones (5a-d) were prepared in high yields by photoinduced [4 + 2]π cycloadduct of N-(ethoxycarbonyl)azepine with substituted cyclopentadienones. The structure of one of the cage ketones (5d) was confirmed by X-ray analysis to be 1,2