Synthesis of isoquinoline derivatives by Diels-Alder reactions of 2(1H)-pyridones having an electron-withdrawing group with methoxy-1,3-butadienes.
Diels-Alder (DA) reactions of 2(1H)-pyridones having an electron-withdrawing group at the 4-position with 2,3-dimethoxy- and 2-methoxy-1,3-butadienes gave isoquinoline derivatives. Furthermore, an isoquinoline alkaloid (6,7-dimethoxy-2-methyl-1(2H)-isoquinolone) was synthesized by elimination of hydrogen cyanide and dehydrogenation of the DA-adduct having a cyano group at the 4a-position.
Fujita
R
R
Tohoku Pharmaceutical University, Sendai, Japan. refujita@tohoku-pharm.ac.jp
Hoshino
M
M
Tomisawa
H
H
Hongo
H
H
D002070:Butadienes / Q000737:chemistry*; D004583:Electrons; D007536:Isomerism; D007546:Isoquinolines / Q000138:chemical synthesis*; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D011728:Pyridones / Q000737:chemistry*; D013055:Spectrophotometry, Infrared
D002070:Butadienes; D007546:Isoquinolines; D011728:Pyridones