Stereochemical Investigation
of the Products of the
Photoinduced Perfluoroalkylation–Dimerization of Anthracene
Emiko Nogami
Takashi Yamazaki
Toshio Kubota
Tomoko Yajima
10.1021/acs.joc.5b01655.s004
https://acs.figshare.com/articles/journal_contribution/Stereochemical_Investigation_of_the_Products_of_the_Photoinduced_Perfluoroalkylation_Dimerization_of_Anthracene/2130205
The
photoinduced perfluoroalkylation of anthracene has been shown
to provide 9,9′,10,10′-tetrahydro-10,10′-diperfluoroalkyl-9,9′-bianthracenes
in over 70% yields, each perfluoroalkyl iodide producing three diastereomers.
The structures of all three diastereomers (<i>cis</i>,<i>cis</i>, <i>cis</i>,<i>trans</i>, and <i>trans</i>,<i>trans</i> isomers) have been elucidated
by both NMR and X-ray crystallographic analyses. Most notably, an
X-ray crystallographic analysis has revealed that the <i>trans</i>,<i>trans</i> diastereomer having the two trifluoromethyl
groups in 10,10′-positions adopts a 74° twisted relationship
of the two dihydroanthracene rings. Furthermore, each of the two <i>trans</i>,<i>trans</i> isomers <b>2a</b>,<b>b</b> has been shown to exist as a mixture of new types of atropisomers
and the energy barrier for the interconversion of the two atropisomers
has been estimated to be 12 kcal/mol by variable-temperature NMR analysis.
2015-09-18 00:00:00
ci
energy barrier
perfluoroalkyl iodide
atropisomer
Stereochemical Investigation
dihydroanthracene rings
diastereomer
isomers
NMR
trifluoromethyl groups
tran
AnthraceneThe photoinduced perfluoroalkylation
analysis