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Facile Synthesis of Polycyclic Aromatic Hydrocarbons: Brønsted Acid Catalyzed Dehydrative Cycloaromatization of Carbonyl Compounds in 1,1,1,3,3,3‐Hexafluoropropan‐2‐ol
Author(s) -
Fujita Takeshi,
Takahashi Ikko,
Hayashi Masaki,
Wang Jingchen,
Fuchibe Kohei,
Ichikawa Junji
Publication year - 2017
Publication title -
european journal of organic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.825
H-Index - 155
eISSN - 1099-0690
pISSN - 1434-193X
DOI - 10.1002/ejoc.201601406
Subject(s) - chemistry , catalysis , brønsted–lowry acid–base theory , organic chemistry , polycyclic aromatic hydrocarbon , medicinal chemistry
The cycloaromatization of aromatic aldehydes and ketones was readily achieved by using a Brønsted acid catalyst in 1,1,1,3,3,3‐hexafluoropropan‐2‐ol (HFIP). In the presence of a catalytic amount of trifluoromethanesulfonic acid, biaryl‐2‐ylacetaldehydes and 2‐benzylbenzaldehydes underwent sequential intramolecular cationic cyclization and dehydration to afford phenacenes and acenes, respectively. Furthermore, biaryl‐2‐ylacetaldehydes bearing a cyclopentene moiety at the α‐position underwent unprecedented cycloaromatization including ring expansion to afford triphenylenes. HFIP effectively promoted the cyclizations by suppressing side reactions presumably as a result of stabilization of the cationic intermediates.