Rearrangement of a 2-methylenecyclobutanone derivative triggered by photoinduced electron transfer: an unprecedented oxa analogue of the tetramethyleneethane radical cation.
On irradiation of p-chloranil (CA), 2,2-bis(p-methoxyphenyl)-3,3-dimethyl-4-methylenecyclobutanone (1) gives 2,2-bis(p-methoxyphenyl)-4-isopropylidenecyclobutanone (2), whereas 2 affords a CA adduct (4), suggesting that a novel rearrangement of 1 to give 2 occurs irreversibly via intermediate 3*+, a radical cation variant of an unprecedented oxa analogue of tetramethyleneethane.
Ikeda
Hiroshi
H
Department of Chemistry, Graduate School of Science, Tohoku University, Sendai 980-8578, Japan. ikeda@org.chem.tohoku.ac.jp
Tanaka
Futoshi
F
Akiyama
Kimio
K
Tero-Kubota
Shozo
S
Miyashi
Tsutomu
T