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6‐Nitro‐1,2,3,4‐tetrahydroquinolines by a tandem reductive amination‐S N Ar reaction
Author(s) -
Bunce Richard A.,
Nago Takahiro
Publication year - 2008
Publication title -
journal of heterocyclic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.321
H-Index - 59
eISSN - 1943-5193
pISSN - 0022-152X
DOI - 10.1002/jhet.5570450433
Subject(s) - chemistry , reductive amination , sodium cyanoborohydride , aldehyde , ketone , nitro , amination , cascade reaction , tandem , organic chemistry , methanol , primary (astronomy) , butanone , combinatorial chemistry , medicinal chemistry , catalysis , solvent , alkyl , materials science , composite material , physics , astronomy
A tandem reductive amination‐S N Ar reaction has been developed for the synthesis of 6‐nitro‐1,2,3,4‐tetrahydroquinolines. Treatment of 4‐(2‐fluoro‐5‐nitrophenyl)‐2‐butanone or 3‐(2‐fluoro‐5‐nitrophenyl)‐propanal with primary amines and sodium cyanoborohydride in methanol at room temperature provided good to excellent yields of the substituted tetrahydroquinolines. The reaction proceeded best with the ketone substrate using primary amines that were unbranched at the α‐carbon. The aldehyde also produced the target heterocycles, but these were accompanied by 10‐15% of the uncyclized side chain reductive amination products.