REMARKABLY FAST CYCLOREVERSION IN METHOXY SUBSTITUTED COOKSON'S CAGE KETONES ASSISTED BY THE CAPTO-DATIVE SUBSTITUENT EFFECT AND BY THE THROUGH-BOND INTERACTION

Article abstract of DOI:10.1016/S0040-4039(00)94163-7

1,7-Dimethoxy groups in Cookson's pentacyclic cage derivates (2 and 5) accelerate the thermal <2+2>cycloreversion, possibly by means of the unusual lengthening of C₁-C₇ bond and the synergetic capto-dative stabilization of 1,4-diradical (7 and 8).