X-ray structural studies on a series of oxygenated anthracene cycloadducts. Evidence for pi-sigma negative homohyperconjugation in the ground state
Application of the variable oxygen probe to low-temperature crystal data from the series of oxygenated anthracene cycloadducts 10-16, revealed a strong response of the C-OR bond distance in these structures to the electron demand of the OR group. It is believed that this represents the manifestation of pi-sigma negative homohyperconjugation in the ground state. Ab initio molecular orbital calculations on the model system 18 provided further support for this.
Pool
BR
School of Chemistry University of Melbourne, Parkville VIC 3010, Australia.
White
JM
Wolynec
PP