204142-61-0Relevant academic research and scientific papers
Thermal and photochemical isomerization of tetraaryl tetrakis(trifluoromethyl)[4]radialenes
Uno, Hidemitsu,Kasahara, Ken-Ichi,Nibu, Nobumasa,Nagaoka, Shin-Ichi,Ono, Noboru
, p. 1615 - 1622 (2000)
The isomerization of tetraaryl tetrakis(trifluoromethyl)[4]radialenes was studied. When type II (all-Z) isomers of 5,6,7,8-tetraaryl-5,6,7,8- tetrakis(trifluoromethyl)[4]radialenes were heated in tetralin at 170-200 °C, isomerization occurred to give mixtures of four [4]radialenes in a ratio of ca. I:II:III:IV = 1:10:5:1. However, when the isomeric mixtures were heated in the solid state at the same temperature, selective isomerization took place to give type II isomers in good selectivity (>91%). Upon irradiation with light, the type II isomers first isomerized to mixtures of the four [4]radialene isomers (I:II:III:IV = 2:2:48:48) and then rearranged to cyclobuta[b]naphthalenes via a 6π-electrocyclic reaction followed by 1,3- hydrogen migration.
