10.1021/jo010579z.s002
Kevin R. Roesch
Kevin R.
Roesch
Richard C. Larock
Richard C.
Larock
Synthesis of Isoquinolines and Pyridines by the Palladium/Copper-Catalyzed Coupling and Cyclization of Terminal
Acetylenes and Unsaturated Imines: The Total Synthesis of
Decumbenine B
American Chemical Society
2001
product decumbenine B
aryl
cyclization conditions
isoquinoline heterocycles
Terminal Acetylenes
alkenyl acetylenes cyclize
terminal acetylenes
terminal acetylene
iminoalkyne
Total Synthesis
yield
palladium catalyst
Decumbenine B Monosubstituted isoquinolines
cyclization methodology
2001-12-12 00:00:00
Journal contribution
https://acs.figshare.com/articles/journal_contribution/Synthesis_of_Isoquinolines_and_Pyridines_by_the_Palladium_Copper-Catalyzed_Coupling_and_Cyclization_of_Terminal_Acetylenes_and_Unsaturated_Imines_The_Total_Synthesis_of_Decumbenine_B/3689907
Monosubstituted isoquinolines and pyridines have been prepared in good to excellent yields via
coupling of terminal acetylenes with the <i>tert</i>-butylimines of <i>o</i>-iodobenzaldehydes and 3-halo-2-alkenals in the presence of a palladium catalyst and subsequent copper-catalyzed cyclization of
the intermediate iminoalkynes. In addition, isoquinoline heterocycles have been prepared in
excellent yields via copper-catalyzed cyclization of iminoalkynes. The choice of cyclization conditions
is dependent upon the nature of the terminal acetylene that is employed, as only aryl and alkenyl
acetylenes cyclize under the palladium-catalyzed reaction conditions that have been developed.
However, aryl-, vinylic-, and alkyl-substituted acetylenes undergo palladium-catalyzed coupling
and subsequent copper-catalyzed cyclization in excellent yields. The total synthesis of the
isoquinoline natural product decumbenine B has been accomplished in seven steps and 20% overall
yield by employing this palladium-catalyzed coupling and cyclization methodology.