ORGANIC
LETTERS
2007
Vol. 9, No. 17
3397-3399
Novel CuO Nanoparticle Catalyzed C
Cross Coupling of Amines with
Iodobenzene
−N
Laxmidhar Rout, Suribabu Jammi, and T. Punniyamurthy*
Department of Chemistry, Indian Institute of Technology Guwahati,
Guwahati 781039, India
Received June 12, 2007
ABSTRACT
CuO nanoparticles catalyze the C
−N cross coupling of amines with iodobenzene in excellent yields. The reaction is simple and efficient and
operates under air with ligand free conditions. The catalyst is recyclable without loss of activity.
The formation of C-N bonds by cross coupling reactions
represents a powerful means for the preparation of numerous
compounds in biological, pharmaceutical, and material
sciences.1 The traditional methods employed for C-N bond
formation, however, often require stoichiometric amounts of
copper reagents, which, on scale-up, leads to the problem
of waste disposal.2 To overcome these drawbacks, consider-
able attention has been recently focused to develop catalytic
systems for this purpose.3 From an industrial standpoint, these
reactions are attractive because the cost and environmental
impact (E-factor) of the process can be reduced.4 In 1983
Migita and co-workers first reported the cross coupling of
tributyltin amide with aryl bromide catalyzed by PdCl2{P(o-
C6H4Me)3}2.5 Palladium complexes bearing sterically hin-
dered phosphine ligands6 and copper complexes having
electron-rich ligands such as diamines,7 ethylene glycol,8a
N,N-diethylsalicylamide,8b 1,10-phenanthroline,9 N-oxime,10
thiophencarboxylate,11 amino acids,12 and 1,3-dicarbonyl
compounds13 have been subsequently studied as catalysts for
amination of aryl halides. Herein, we report that CuO
nanoparticles (Aldrich: particle size 33 nm and surface area
29 m2/g) catalyze efficiently the C-N cross coupling of
amines with iodobenzene in excellent yields. The reactions
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10.1021/ol0713887 CCC: $37.00
© 2007 American Chemical Society
Published on Web 07/18/2007