1-(2′-Anilinyl)prop-2-yn-1-ol Rearrangement for Oxindole Synthesis
作者:Prasath Kothandaraman、Bing Qin Koh、Taweetham Limpanuparb、Hajime Hirao、Philip Wai Hong Chan
DOI:10.1002/chem.201202606
日期:2013.2.4
on NIS (N‐iodosuccinimide)‐mediated cycloisomerization reactions of 1‐(2′‐anilinyl)prop‐2‐yn‐1‐ols to gem‐3‐(diiodomethyl)indolin‐2‐ones and 2‐(iodomethylene)indolin‐3‐ones has been developed. The reactions were shown to be chemoselective, with secondary and tertiary alcoholic substrates exclusively giving the 3‐ and 2‐oxindole products, respectively. In the case of the latter, the transformation features
Silver Triflate Catalyzed Tandem Heterocyclization/Alkynylation of 1-((2-Tosylamino)aryl)but-2-yne-1,4-diols to 2-Alkynyl Indoles
作者:Srinivasa Reddy Mothe、Prasath Kothandaraman、Sherman Jun Liang Lauw、Samuel Ming Wei Chin、Philip Wai Hong Chan
DOI:10.1002/chem.201200578
日期:2012.5.14
Don't cross me! 2‐Alkynyl indoles were prepared efficiently by the AgOTf‐catalyzedtandemheterocyclization/alkynylation of 1‐(2‐tosylamino)aryl)but‐2‐yne‐1,4‐diols under mild conditions (see scheme). The attractiveness of this approach lies in the fact that both the indole ring and alkyne side chain of the N‐heterocycle are sequentially formed from low cost, readily available, and ecologically benign
Metal-free synthesis of 1H-indole-2-carbaldehydes by N-iodosuccinimide-mediated cyclization of 1-(2′-anilinyl)prop-2-yn-1-ols in water. A formal synthesis of (R)-calindol
作者:Prasath Kothandaraman、Sherman Jun Liang Lauw、Philip Wai Hong Chan
DOI:10.1016/j.tet.2013.06.032
日期:2013.9
cycloisomerization of 1-(2-aminophenyl)prop-2-yn-1-ols is described. The reaction is operationally straightforward and accomplished in good to excellent yields (48–91%) from a wide range of alcohol substrates that are low cost, easily accessible, and ecologically benign. The utility of the approach as a potential scale-up strategy for the synthesis of the indole was exemplified by the large-scale synthesis of one