method usually involves acid- or base-catalyzed or thermal (up
to 250 °C) condensation between a 2-aminoaryl ketone or
aldehyde and a second carbonyl compound possessing a reactive
R-methylene group, followed by cyclodehydration. However,
most of the synthetic approaches reported so far have suffered
from the need of high temperatures and the use of hazardous
and expensive catalysts,8 Therefore, the development of a
general, efficient, and conventional method for highly substituted
3-quinolinecarboxylic esters is highly desirable.
Cascade Synthesis of 3-Quinolinecarboxylic Ester
via Benzylation/ Propargylation-Cyclization
Jinmin Fan, Changfeng Wan, Gaojun Sun, and
Zhiyong Wang*
Hefei National Laboratory for Physical Science at
Microscale, Joint laboratory of Green Synthetic Chemistry
and Department of Chemistry, UniVersity of Science and
Technology of China, Hefei, Anhui 230026, P. R. China
In recent years, benzylic alcohols and their derivatives have
received considerable attention as carbon electrophiles capable
ofreactingwithvariouscarbon,oxygen,andsulfurnucleophiles.9,10
Herein, we present a novel approach to synthesize highly
substituted 3-quinolinecarboxylic acid with a readily available
ReceiVed August 11, 2008
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Quinolines and their derivatives occur widely in natural
products and have attracted considerable attention due to their
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10.1021/jo8017654 CCC: $40.75 2008 American Chemical Society
Published on Web 10/04/2008