Steric effects in hula-twist photoisomerization. 1,4-dimethyl- and 2,3-dimethyl-1,4-diphenylbutadienes.
1,4-Dimethyl-1,4-diphenylbutadiene was shown to be able to execute regiospecific HT-1 photoisomerization around a methyl group when irradiated in a low-temperature organic glass, albeit at reduced efficiency. 2,3-Dimethyl-1,4-diphenylbutadiene exhibited a different type of steric effect, causing the E,E-isomer to undergo regiospecific HT-1 photoisomerization.
Yang
Lan-Ying
LY
Department of Chemistry, University of Hawaii, 2545 The Mall, Honolulu, Hawaii 96822, USA.
Liu
Robert S H
RS
Wendt
Natalie L
NL
Liu
Jin
J