Photoisomerization of stilbene dendrimers: the need for a volume-conserving isomerization mechanisms.
Highly branched stilbene dendrimers were synthesized and their photochemical behavior was studied. Even the stilbene dendrimer with molecular weight over 6500 underwent trans-cis isomerization in the excited singlet state within the lifetime of 10 ns. The photoisomerization of C=C double bond of stilbene dendrimers in the excited state may proceed by a volume-conserving novel mechanism such as hula-twist rather than conventional 180 degrees rotation around the C=C double bond based on fluorescence and isomerization experiments.
Uda
Mayuko
M
Department of Chemistry, University of Tsukuba, Tsukuba, Ibaraki, Japan.
Mizutani
Takuo
T
Hayakawa
Junpel
J
Momotake
Atsuya
A
Ikegami
Masashi
M
Nagahata
Ritsuko
R
Arai
Tatsuo
T