Categories: Synthesis of N-Heterocycles >
Synthesis of indolizines
Recent Literature
Organocopper reagents smoothly react with heterocyclic propargyl mesylates at
low temperature to produce N-fused heterocycles. The copper reagent generates
allenyl intermediates in situ via SN2'-substitution and copper
byproducts also mediate the subsequent cycloisomerization step.
D. Chernyak, S. B. Gadamsetty, V. Gevorgyan, Org. Lett., 2008,
10, 2307-2310.
An efficient and one-step synthesis of 3-aminoindolizines or benz[e]indolizines
from the reactions of propargyl amines or amides with heteroaryl bromides is
realized by a tandem reaction using Pd/Cu catalysts, which catalyze coupling and
cycloisomerization reactions in the same vessel.
Y. Liu, Z. Song, B. Yan, Org. Lett., 2007,
9, 409-412.
A gold(III)-catalyzed multicomponent coupling/cycloisomerization reaction of
heteroaryl aldehydes, amines, and alkynes under solvent-free conditions or in
water provides rapid access to substituted aminoindolizines with high atom
economy and high catalytic efficiency.
B. Yan, Y. Liu, Org. Lett., 2007,
9, 4323-4326.
A copper-catalyzed cycloisomerization of 2-pyridyl-substituted propargylic
acetates and its derivatives offers an efficient route to C-1 oxygenated
indolizines with a wide range of substituents under mild reaction conditions.
The presented method could be readily applied to the synthesis of indolizinones
through a cyclization/1,2-migration of tertiary propargylic alcohols.
B. Yan, Y. Zhou, H. Zhang, J. Chen, Y. Liu, J. Org. Chem.,
2007,
72, 7783-7786.
An Au-catalyzed synthesis of fused pyrroloheterocycles from diverse
propargyl-substituted heterocycles proceeds via alkyne-vinylidene
isomerization with concomitant 1,2-shift of hydrogen, silyl, and stannyl
groups. This method allows for mild and efficient synthesis of diverse C-2
substituted N-heterocycles.
I. V. Seregin, V. Gevorgyan, J. Am. Chem. Soc., 2006, 128, 12050-12051.
