Categories: C=O Bond Formation >
Synthesis of amides
Name Reactions
Recent Literature
A simple ruthenium catalyst mediates a direct coupling between an alcohol and an
amine with the liberation of two molecules of dihydrogen. The active catalyst is
generated in situ from an easily available ruthenium complex, an N-heterocyclic
carbene and a phosphine. The reaction allows primary alcohols to be coupled with
primary alkylamines to afford secondary amides in good yields.
L. U. Nordstrøm, H. Vogt, R. Madsen, J. Am. Chem. Soc., 2008,
130, 17672-17673.
An in situ generated catalyst from readily available RuH2(PPh3)4,
an N-heterocyclic carbene (NHC) precursor, NaH, and acetonitrile showed
high activity for the amide synthesis directly from either alcohols or aldehydes
with amines.
S. Muthaiah, S. C. Ghosh, J.-E. Jee, C. Chen, J. Zahng, S. H. Hong, J. Org. Chem., 2010,
75, 3002-3006.
An iodine-NH3 • H2O system enables a direct transformation
of aryl, heteroaryl, vinyl, or ethynyl methyl ketones or carbinols to the
corresponding primary amides in good yields in aqueous media. A tandem
Lieben-Haller-Bauer reaction mechanism is proposed.
L. Cao, J. Ding, M. Gao, Z. Wang, J. Li, A. Wu, Org. Lett., 2009,
11, 3810-3813.
Sodium perborate in acetic acid is an effective reagent for the oxidation of
aromatic aldehydes to carboxylic acids, iodoarenes to (diacetoxyiodo)arenes,
azines to N-oxides, and various sulphur heterocycles to S,S-dioxides.
Nitriles undergo smooth oxidative hydration to amides when aqueous methanol
is employed as solvent.
A. McKillop, D. Kemp, Tetrahedron, 1989,
45, 3299-3306.
Ru(OH)x / Al2O3 acts as a heterogeneous
catalyst for the hydration of activated and unactivated nitriles in water.
This reaction can be performed with high selectivity and conversion to give
amides. Furthermore, catalyst/product separation is easy and Ru(OH)x
/ Al2O3 is recyclable.
K. Yamaguchi, M. Matsushita, N. Mizuno, Angew. Chem. Int. Ed., 2004,
43, 1576-1580.
The use of acetaldoxime as the water source in the presence of a Rh catalyst
allows the conversion of various nitriles to amides under neutral and anhydrous
conditions. The reaction displays excellent compatibility with acid or base
labile and hydrolytically labile functional groups.
J. Lee, M. Kim., S. Chang, H.-Y. Lee, Org. Lett., 2009,
11, 5598-5601.
A wide range of aldoximes has been converted into the corresponding amides in
high yield and selectivity using the ruthenium-based catalyst Ru(PPh3)3(CO)H2/dppe/TsOH
with catalyst loading as low as 0.04 mol%.
N. A. Owston, A. J. Parker, J. M. J. Williams, Org. Lett., 2007,
9, 3599-3601.
[Ir(Cp*)Cl2]2 catalyzes the rearrangement of oximes to
furnish amides. An iridium-catalyzed transfer
hydrogenation between alcohols and styrene and the subsequent formation of an
oxime allows the conversion of alcohols
into amides in a one-pot process.
N. A. Owston, A. J. Parker, J. M. J. Williams, Org. Lett., 2007,
9, 73-75.
N. A. Owston, A. J. Parker, J. M. J. Williams, Org. Lett., 2007,
9, 73-75.
In the presence of hydrogen peroxide and trimethylsilyl chloride, thiocarbonyls
desulfurize to the corresponding carbonyls in short reaction times with no side
reactions and excellent selectivity. This process is a safe, operationally
simple, and environmentally benign alternative for the desulfurization of
thiocarbonyls.
K. Bahrami, M. M. Khodaei, M. Tajik, Synthesis, 2010,
4282-4286.
Desulfurization of thioamides was accomplished using a semicatalytic amount of
Bu4NBr. The corresponding amides were obtained in high yields, with
good functional group compatibility.
K. Inamoto, M. Shiraishi, K. Hiroya, T. Doi, Synthesis, 2010,
3087-3090.
The hydrogen peroxide-zirconium(IV) chloride reagent system is efficient and
general for the conversion of thioamides to amides in short reaction times and
good chemoselectivity, and allows a simple workup that precludes the use of
toxic solvents.
K. Bahrami, M. M. Khodaei, Y. Tirandaz, Synthesis, 2009,
369-371.
Several amides were obtained in high yields by an efficient method from
the corresponding imines which are readily prepared from aldehydes. This
procedure involves the oxidation of aldimines with m-CPBA and BF3·OEt2.
In this reaction, the product is strongly influenced by the electron
releasing capacity of the aromatic substituent (Ar).
G. An, M. Kim, J. Y. Kim, H. Rhee, Tetrahedron Lett., 2003,
44, 2183-2186.
