1315477-50-9Relevant academic research and scientific papers
1-(2′-Anilinyl)prop-2-yn-1-ol rearrangement for oxindole synthesis
Kothandaraman, Prasath,Koh, Bing Qin,Limpanuparb, Taweetham,Hirao, Hajime,Chan, Philip Wai Hong
, p. 1978 - 1985 (2013/03/14)
A synthetic method that relies 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 an unprecedented double 1,2-OH and 1,2-alkyl migration relay. Density functional theory (DFT) calculations based on proposed iodoaminocyclization species provide insight into this unique divergence in product selectivity. Copyright
Gold-catalyzed cycloisomerizations of 1-(2-(Tosylamino)phenyl)prop-2-yn-1- ols to 1H-Indole-2-carbaldehydes and (E)-2-(Iodomethylene)Indolin-3-ols
Kothandaraman, Prasath,Mothe, Srinivasa Reddy,Toh, Sharon Si Min,Chan, Philip Wai Hong
, p. 7633 - 7640 (2011/11/12)
A method to prepare lH-indole-2-carbaldehydes and (E)-2-(iodomethylene) indolin-3-ols by gold(I)-catalyzed cycloisomerization of l-(2-(tosylamino) phenyl)prop-2-yn-1-ols with N-iodosuccinimide (NIS) is reported. The reactions were shown to be operationally simplistic and proceed efficiently for a wide variety of substrates, affording the corresponding products in good to excellent yields (70-99%). The mechanism is suggested to involve activation of the alkyne moiety of the substrate by the gold(I) catalyst. This triggers intramolecular addition of the tethered aniline moiety to give a vinyl gold intermediate, which undergoes iododeauration with NIS to give the (E)-2-(iodomethylene)indolin-3-ol adduct. Subsequent 1,3-allylic alcohol isomerization (1,3-AAI) followed by formylation of this vinyl iodide intermediate then gives the 1H-indole-2-carbaldehyde.
