Categories: C-H Bond Formation >
Reduction of Alkenes
Recent Literature

In situ preparation of an active Pd/C catalyst from Pd(OAc)2 and
charcoal in methanol enables a simple, highly reproducible protocol for the
hydrogenation of alkenes and alkynes and for the hydrogenolysis of O-benzyl
ethers. Mild reaction conditions and low catalyst loadings, as well as the
absence of contamination of the product by palladium residues, make this a
sustainable, useful process.
F.-X. Felpin, E. Fouquet, Chem. Eur. J., 2010,
12440-12445.

A Pd/C-catalyzed hydrogenation using diphenylsulfide as a catalyst poison
selectively reduces olefin and acetylene functionalities without
hydrogenolysis of aromatic carbonyls and halogens, benzyl esters, and N-Cbz
protective groups.
A. Mori, Y. Miyakawa, E. Ohashi, T. Haga, T. Maegawa, H. Sajiki, Org.
Lett.,
2006,
8, 3279-3281.

Pd/P(t-Bu)3 is an efficient and mild catalyst for selective
reduction of various alkenes under transfer-hydrogenation conditions leading to
the corresponding saturated derivatives in good yields.
J. M. Brunel, Synlett, 2007, 330-332.

A palladium-fibroin complex catalyzed the chemoselective
hydrogenation of acetylenes, olefins and azides in the presence of aromatic
ketones and aldehydes, halides, N-Cbz protective groups and benzyl esters which
are readily hydrogenated using Pd/C or Pd/C(en) as a catalyst.
T. Ikawa, H. Sajiki, K. Hirota, Tetrahedron, 2005,
61, 2217-2231.

A generally applicable method for the introduction of gaseous hydrogen into a
sealed reaction system under microwave irradiation allows the hydrogenation of
various substrates in short reaction times with moderate temperatures between 80
°C and 100 °C with 50 psi of hydrogen.
G. S. Vanier, Synlett, 2007, 131-135.

Various carbon-carbon double bonds in olefins and α,β-unsaturated ketones
were effectively reduced to the corresponding alkanes and saturated ketones,
using ammonium formate as a hydrogen transfer agent in the presence of Pd/C
as catalyst in refluxing methanol.
Z. Paryzek, H. Koenig, B. Tabacka, Synthesis,
2003, 2023-2026.

A new recyclable catalyst composed of palladium nanoparticles dispersed in
an organic polymer was synthesized by a simple procedure from readily
available reagents. This catalyst is robust, and highly active in many
organic transformations including alkene and alkyne hydrogenation,
carbon-carbon cross-coupling reactions, and aerobic alcohol oxidation.
C. M. Park, M. S. Kwon, J. Park,
Synthesis, 2006, 3790-3794.

A one-pot, three-step strategy for the regioselective semihydrogenation of
dienes uses 9-BBN-H as a temporary protective group for alkenes. Yields range
from 55% to 95%, and the reaction tolerates various common functional groups.
Additionally, the final elimination step of the sequence can be replaced with a
peroxide-mediated alkylborane oxidation, generating regioselectively alcohols.
T. J. A. Graham, T. H. Poole, C. N. Reese, B. C. Goess, J. Org. Chem., 2011,
76, 4132-4138.

In situ generation of molecular hydrogen by addition of triethylsilane to
palladium on charcoal results in rapid and efficient reduction of multiple bonds,
azides, imines, and nitro groups, as well as deprotection of benzyl and allyl
groups under mild, neutral conditions.
P. K. Mandal, J. S. McMurray, J. Org. Chem.,
2007,
72, 6599-6601.

Poly(ethylene glycol) (PEG) (400) has been found to be a superior solvent
over ionic liquids by severalfold in promoting the hydrogenation of various
functional groups using Adams' catalyst. Both the catalyst and PEG were
recycled efficiently over 10 runs without loss of activity, and without
substrate cross contamination.
S. Chandrasekhar, S. Y. Prakash, C. L. Rao, J. Org. Chem., 2006,
71, 2196-2199.

A one-pot protocol for the formation of 2-nitrobenzenesulfonylhydrazide (NBSH)
from commercial reagents and subsequent alkene reduction is operationally simple
and generally efficient. A range of 16 substrates have been reduced,
highlighting the unique chemoselectivity of diimide as a alkene reduction
system.
B. J. Marsh, D. R. Carbery, J. Org. Chem., 2009,
74, 3186-3188.

Various olefins can be hydrogenated quantitatively with neutral, flavin-derived
catalysts in the presence of hydrazine under an under an athomspheric pressure
of O2. A vitamin B2 derivative acts as a highly efficient
and robust catalyst for the an environmentally benign process producing water
and nitrogen gas as the only waste products.
Y. Imada, T. Kitagawa, T. Ohno, H. Iida, T. Naota, Org. Lett., 2010,
12, 32-35.

Olefins can be hydrogenated by treatment with hydrazine in the presence of a
5-ethyl-3-methyllumiflavinium perchlorate catalyst under O2
atmosphere to give the corresponding hydrogenated products in excellent
yields along with environmentally benign water and molecular nitrogen as the
only waste products.
Y. Imada, H. Iida, T. Naota, J. Am. Chem. Soc.,
2005,
127, 14544-14545.

A microwave-assisted, palladium-catalyzed catalytic transfer hydrogenation
of different homo- or heteronuclear organic compounds using formate salts as
a hydrogen source was performed in ([bmim][PF6]. Essentially pure
products could be isolated in moderate to excellent yields by simple
liquid-liquid extraction.
H. Berthold, T. Schotten, H. Hönig, Synthesis,
2002, 1607-1610.

The preparation of alkenyl halides of any length from inexpensive starting
reagents is reported. Standard organic transformations were used to prepare
straight-chain α-olefin halides in excellent overall yields with no
detectable olefin isomerization and full recovery of any unreacted starting
material.
T. W. Baughman, J. C. Sworen, K. B. Wagener, Tetrahedron, 2004,
60, 10943-10948.

Nanopalladium particles supported on a amphiphilic polystyrene-poly(ethylene
glycol) resin catalyzed hydrogenation of olefins and hydrodechlorination of
chloroarenes under aqueous conditions.
R. Nakao, H. Rhee, Y. Uozumi, Org. Lett., 2005,
7, 163-165.

Reduction of stilbenes with Na metal in dry THF allowed easy access to various
1,2-diaryl-1,2-disodiumethanes. These diorganometallic intermediates gave
1,2-diarylethanes upon aqueous work up, or trans-1,2-diaryl-substituted
cyclopentanes by cycloalkylation with 1,3-dichloropropanes.
U. Azzena, G. Dettori, C. Lubinu, A. Mannu, L. Pisano, Tetrahedron, 2005,
61, 8663-8668.

A catalytic system of cobalt(II) chloride and diisopropylamine in combination
with NaBH4 showed excellent activity in the chemoselective reduction
of various carboxylic esters to their corresponding alcohols in very good
yields under mild conditions. Unsaturated carboxylic esters give saturated
alcohols in high yields.
A. R. Jagdale, A. S. Paraskar, A. Sudalai, Synthesis, 2009,
660-664.

Ammonia, pyridine and ammonium acetate were extremely effective
as inhibitors of Pd/C catalyzed benzyl ether hydrogenolysis. While olefin, Cbz,
benzyl ester and azide functionalities were hydrogenated smoothly, benzyl ethers
were not cleaved.
H. Sajiki, Tetrahedron Lett., 1995,
36, 3465-3468.

Selective hydrogenation conditions of olefin, benzyl ether and acetylene
functionalities in the presence of TBDMS or TES ether have been developed.
H. Sajiki, T. Ikawa, K. Hattori, K. Hirota, Chem. Commun., 2003,
654-655.

A mild catalytic asymmetric transfer hydrogenation of β,β-disubstituted
nitroalkenes using formic acid as reductant in combination with an Ir catalyst
is conducted in water at low pH and open to air to give products in good yield
and selectivity.
O. Soltani, M. A. Ariger, E. M. Carreira, Org. Lett., 2009,
11, 4196-4198.

A highly enantioselective hydrogenation of enamides is catalyzed by a dual
chiral-achiral acid system. By employing a substoichiometric amount of a chiral
phosphoric acid and acetic acid, low catalyst loadings of the chiral catalyst
were sufficient to provide excellent yield and enantioselectivity of the
reduction product.
G. Li, J. C. Antilla, Org. Lett., 2009,
11, 1075-1078.
