Rhenium-catalyzed regioselective synthesis of multisubstituted pyridines from β-enamino ketones and alkynes via C-C bond cleavage.
A new method is described for the regioselective synthesis of multisubstituted pyridine derivatives. Treatment of N-acetyl β-enamino ketones with alkynes in the presence of the rhenium catalyst, Re(2)(CO)(10), gives multisubstituted pyridines regioselectively. In this reaction, the N-acetyl moieties are important for the selective formation of the multisubstituted pyridines. This reaction proceeds via insertion of alkynes into a carbon-carbon single bond of β-enamino ketones, intramolecular nucleophilic cyclization, and elimination of acetic acid.
Division of Chemistry and Biotechnology, Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushimanaka, Okayama 700-8530, Japan.
Shun-ichi
S
Yamamoto
Kana
K
Okamoto
Makiko
M
Murakoso
Yoichiro
Y
Kuninobu
Kazuhiko
K
Takai