Straightforward Access to 2-Iodoindolizines via Iodine-Mediated Cyclization of 2-Pyridylallenes
摘要:
A metal-free access to 2-iodo-1,3-disubstituted indolizines has been developed. The proposed synthesis is relatively simple and efficient and involves the iodine-triggered 5-endo-trig cyclization of 2-pyridylallene precursors. While it can be conducted on a gram scale, the preparation of the precursors is straightforward and does not always require intermediate purifications. The obtained 2-iodoindolizines can be further functionalized through cross-coupling reactions.
Pt-Catalyzed Cyclization/1,2-Migration for the Synthesis of Indolizines, Pyrrolones, and Indolizinones
摘要:
Indolizine, pyrrolone, and indolizinone heterocycles are easily accessed via the Pt(II)-catalyzed cycloisomerization or a tandem cyclization/1,2-migration of pyridine propargylic alcohols and derivatives. This method provides an efficient synthesis of highly functionalized heterocycles from readily available substrates.
Pt-Catalyzed Cyclization/1,2-Migration for the Synthesis of Indolizines, Pyrrolones, and Indolizinones
作者:Cameron R. Smith、Eric M. Bunnelle、Allison J. Rhodes、Richmond Sarpong
DOI:10.1021/ol0701971
日期:2007.3.1
Indolizine, pyrrolone, and indolizinone heterocycles are easily accessed via the Pt(II)-catalyzed cycloisomerization or a tandem cyclization/1,2-migration of pyridine propargylic alcohols and derivatives. This method provides an efficient synthesis of highly functionalized heterocycles from readily available substrates.
Highly Efficient Synthesis of Functionalized Indolizines and Indolizinones by Copper-Catalyzed Cycloisomerizations of Propargylic Pyridines
作者:Bin Yan、Yebing Zhou、Hao Zhang、Jingjin Chen、Yuanhong Liu
DOI:10.1021/jo070983j
日期:2007.9.1
[GRAPHICS]The copper-catalyzed cycloisomerizations of 2-pyridyl-substituted propargylic acetates and its derivatives are described, which offer 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.
Pt-catalyzed cyclization/migration of propargylic alcohols for the synthesis of 3(2H)-furanones, pyrrolones, indolizines, and indolizinones
作者:Eric M. Bunnelle、Cameron R. Smith、Sharon K. Lee、Surendra W. Singaram、Allison J. Rhodes、Richmond Sarpong
DOI:10.1016/j.tet.2008.02.103
日期:2008.7
Several heterocycles such as furanones, pyrrolones, and indolizines, which are of pharmacological importance, are easily accessed via the Pt(II)-catalyzed heterocyclization/1,2-migration of propargylic ketols or hydroxy imine derivatives. This method sidesteps the challenges of traditional heteroaromatic oxygenation strategies such as regioselectivity and functional group tolerance in the syntheses of these heterocycles. (C) 2008 Elsevier Ltd. All rights reserved.
Straightforward Access to 2-Iodoindolizines via Iodine-Mediated Cyclization of 2-Pyridylallenes
A metal-free access to 2-iodo-1,3-disubstituted indolizines has been developed. The proposed synthesis is relatively simple and efficient and involves the iodine-triggered 5-endo-trig cyclization of 2-pyridylallene precursors. While it can be conducted on a gram scale, the preparation of the precursors is straightforward and does not always require intermediate purifications. The obtained 2-iodoindolizines can be further functionalized through cross-coupling reactions.