Et3N-induced demethylation-annulation of 3-alkynyl-4-methoxy-2-pyridones and structurally related compounds in the synthesis of furan-fused heterocycles.
Various 3-iodo-4-methoxypyridin-2-ones and related pyrone and coumarin derivatives have been demonstrated as readily available precursors of 2-substituted furan-fused heterocycles by means of in situ sequential Sonogashira-acetylide coupling, dealkylation, and regioselective furan annulation reactions. A Et3N-induced S(N)2 process has been established that accounts for the dealkylation process.
Conreaux
David
D
ICBMS, Institut de Chimie et Biochimie Moléculaire et Supramoléculaire, CNRS UMR 5246, Université Lyon 1, ESCPE Lyon. 43, Bd du 11 Novembre 1918, 69622 Villeurbanne, France.
Belot
Sébastien
S
Desbordes
Philippe
P
Monteiro
Nuno
N
Balme
Geneviève
G
D003374:Coumarins; D005021:Ethylamines; D005663:Furans / Q000737:chemistry*; D006571:Heterocyclic Compounds / Q000737:chemistry*; D011728:Pyridones / Q000737:chemistry*; D011753:Pyrones
D003374:Coumarins; D005021:Ethylamines; D005663:Furans; D006571:Heterocyclic Compounds; D011728:Pyridones; D011753:Pyrones; C039281:furan; C016162:triethylamine