Categories: Synthesis of N-Heterocycles >
Synthesis of indolines
Recent Literature
Pd(II)-catalyzed intramolecular amination of arenes using either Ce(SO4)2
as
a one- or
N-fluoro-2,4,6-trimethylpyridinium triflate as a two-electron oxidant tolerates a wide range of
functional groups including acetyl, cyano, and nitro. This catalytic
reaction allows expedient syntheses of broadly useful substituted indolines or
indoles.
T.-S. Mei, X. Wang, J.-Q. Yu, J. Am. Chem. Soc., 2009,
131, 10806-10807.
The use of N,N′-bis(2,6-diisopropylphenyl)dihydroimidazol-2-ylidene (SIPr)
as a ligand and tBuONa as the base for sequential palladium-catalyzed
intra- followed by intermolecular aryl amination enables the synthesis of
N-arylated five-, six- and seven-membered nitrogen heterocycles.
R. Omar-Amrani, R. Schneider, Y. Fort, Synthesis,
2004, 2257-2534.
A Pd-catalyzed intermolecular 1,2-carboamination route to indolines from N-aryl
ureas and 1,3-dienes proceeds under mild conditions in relatively nonacidic
media via a C-H insertion/carbopalladation/nucleophilic displacement process.
The in situ generation, or preformation of a palladium tosylate emerges as a key
parameter in gaining the requisite reactivity.
C. E. Houlden, C. D. Bailey, J. G. Ford, M. R. Gagné, G. C. Lloyd-Jones, K. I.
Booker-Milburn, J. Am. Chem. Soc., 2008,
130, 10066-10067.
An efficient, palladium-catalyzed reduction of N-(tert-butoxycarbonyl)indoles
gives N-(tert-butoxycarbonyl)indolines in good yields in the presence of
polymethylhydrosiloxane (PMHS) as reducing agent at room temperature.
S. Chandrasekhar, D. Basu, C. R. Reddy, Synthesis, 2007,
1509-1512.
A Brønsted acid catalyzed transfer hydrogenation of indole derivatives with
Hantzsch dihydropyridine as the hydrogen source enables an efficient synthesis
of various optically active indolines with high enantioselectivities.
M. Rueping, C. Brinkmann, A. P. Antonchick, I. Atoresei, Org. Lett., 2010,
12, 4604-4607.
