Categories: C-O Bond Formation > Synthesis of carboxylic acids >
Synthesis of carboxylic acids by oxidation of aldehydes
Related |
|
Recent Literature
Highly efficient, mild, and simple protocols allow the oxidation of aldehydes
to carboxylic acids and esters utilizing Oxone as the sole oxidant. These
reactions may prove to be valuable alternatives to traditional
metal-mediated oxidations.
B. R. Travis, M. Sivakumar, G. O. Hollist, B. Borhan, Org. Lett., 2003,
5, 1031-1034.
A facile and quantitative preparation of carboxylic acids by a pyridinium
chlorochromate (PCC) catalyzed (2 mol%) oxidation of primary alcohols and
aldehydes using 2.2 equivalents and 1.1 equivalents of H5IO6, respectively, in
acetonitrile is described here.
M. Hunsen,
Synthesis, 2005, 2487-2490.
An aerobic oxidation of a wide range of aldehydes to carboxylic acids in both
organic solvent and water under mild conditions is catalyzed by 5 mol % N-hydroxyphthalimide
(NHPI)
as the organocatalyst in the presence of oxygen as the sole oxidant. No
transition metals or hazardous oxidants or cocatalysts were involved.
P.-F. Dai, J.-P. Qu, Y.-B. Kang, Org. Lett., 2019, 21,
1393-1396.
VO(acac)2 catalyzes the oxidation of aromatic and aliphatic aldehydes
to the corresponding acids efficiently and selectively in the presence of
hydrogen peroxide as an oxidant. This method offers functional-group
compatibility, easy workup procedure, and a short reaction time. The performance
of titania-supported VO(acac)2 in the oxidation of aldehydes was also
investigated.
D. Talukdar, K. Sharma, S. K. Bharadwaj, A. J. Thakur, Synlett, 2013, 24,
963-966.
An N-heterocyclic carbene (NHC) organocatalytic aerobic oxidation of aldehydes
provides the corresponding carboxylic acids under mild reaction conditions.
Remarkably, this method enables an efficient conversion of different classes of
aldehydes including highly challenging electron-rich aryl aldehydes, ortho-substituted
aryl aldehydes, various heteroaromatic aldehydes and α,β-unsaturated aldehydes.
A. K. Khatana, V. Singh, M. K. Gupta, B. Tiwari, Synthesis, 2018, 50,
4290-4294.
A metal-free, chemoselective oxidation of primary alcohols and aldehydes with
cheap 1-hydroxycyclohexyl phenyl ketone as oxidant to the corresponding
carboxylic acids features an easy to handle procedure, high isolated yields, and
good to excellent functional group tolerance even in the presence of vulnerable
secondary alcohols and tert-butanesulfinamides.
W.-Y. Tan, Y. Lu, J.-F. Zhao, W. Chen, H. Zhang, Org. Lett., 2021, 23,
6648-6653.
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.
A convenient and efficient oxidation of hydroxylated and methoxylated
benzaldehydes and acetophenones to the corresponding phenols uses hydrogen
peroxide and methyltrioxorhenium as catalyst in ionic liquids [bmim]BF4
and [bmim]PF6.
R. Bernini, A. Coratti, G. Provenzano, G. Fabrizi, D. Tofani, Tetrahedron, 2005,
61, 1821-1825.
In an efficient and easily scalable continuous flow transformation of alcohols
and aldehydes to carboxylic acids and nitroalkane derivatives to the
corresponding carbonyls and carboxylic acids using permanganate as the oxidant,
the generation and downstream processing of MnO2 slurries was not
found to cause any blocking of the reactor when ultrasound pulses were applied
to the flow system.
J. Sedelmeier, S. V. Ley, I. R. Baxendale, M. Baumann, Org. Lett., 2010,
12, 3618-3621.
Asymmetric hydration of α,α-dichloro aldehydes and α-halo enals via a
NHC-catalyzed redox process gives enantioenriched α-chloro and α-fluoro
carboxylic acids. The reaction allows the installation of an α-deuterium to give
α-deutero α-halo acids using D2O as the deuteron source.
H. U. Vora, T. Rovis, J. Am. Chem. Soc., 2010,
132, 2860-2861.
A direct enantioselective α-hydroxymethylation of aldehydes employing an
α,α-diarylprolinol trimethylsilyl ether organocatalyst enables efficient access
to β-hydroxycarboxylic acids and δ-hydroxy-α,β-unsaturated esters via an
intermediate lactol in good yields, excellent enantioselectivity, and
compatibility with a broad range of functional groups in the aldehyde.
R. K. Boeckman, K. F. Biegasiewicz, D. J. Tusch, J. R. Miller, J. Org. Chem.,
2015,
80, 4030-4045.