Categories: N-H Bond Formation >
Reduction of azides
Recent Literature
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 nickel boride catalyst prepared in situ from NiCl2 and sodium
borohydride allowed facile reductions of a wide range of nitroarenes, aliphatic
nitro compounds, and organic azides. Addition of modified nanocellulose enabled
lower catalyst loading in nitro reductions. The protocols are compatible with a
one-pot Boc-protection to provide the corresponding carbamates.
G. Proietti, K. J. Prathap, X. Yu, R. T. Olsson, P. Dinér, Synthesis, 2022, 54,
133-146.
Tin(IV) 1,2-benzenedithiolate catalyzes the conversion of azides to amines in
the presence of NaBH4. Primary, secondary, tertiary, aromatic, and
heteroaromatic azides are reduced in excellent yields under very mild conditions.
I. Bosch, A. M. Costa, M. Martín, F. Urpí, J. Vilarrasa,
Org. Lett., 2000, 2, 397-399.
Organic azides are easily and chemoselectively reduced to the corresponding amines by reaction
with dichloroindium hydride under very mild conditions. γ-Azidonitriles
give pyrrolidin-2-imines in an outstanding
cyclization.
L. Benati, G. Bencivenni, R. Leardini, D. Nanni, M. Minozzi, P. Spagnolo, R.
Scialpi, G. Zanardi, Org. Lett.,
2006, 8, 2499-2502.
A selective and facile method allows the reduction of aromatic azides to amines
by employing borontrifluoride diethyl etherate and sodium iodide. This
methodology has been applied towards the preparation of biologically important
imine-containing pyrrolobenzodiazepines and their dilactams through an
intramolecular reductive-cyclization process.
A. Kamal, N. Shankaraiah, N. Markandeya, Ch. S. Reddy, Synlett, 2008,
1297-1300.
Aryl azides undergo clean reduction by copper nanoparticles in water in the
presence of ammonium formate. The surface hydrogen on copper nanoparticles is
considered to be the active reducing species. Various functionalized aryl azides
and aryl sulfonyl azides are reduced to the corresponding amines with excellent
chemoselectivity in high yields.
S. Ahammed, A. Saha, B. C. Ranu, J. Org. Chem., 2011,
76, 7235-7239.
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.
A novel enantioselective synthesis of α-amino acids has been developed,
which is broad in scope, simple in application, and advantageous for many α-amino acids
of interest in chemistry, biology, medicine.
E. J. Corey, J. O. Link, J. Am. Chem. Soc., 1992,
114, 1906-1908.
(Me3Si)3SiH was successfully used in various radical-based
transformations in water. The system comprising substrate, silane, and initiator
(ACCN) mixed in aqueous medium at 100°C worked well for both hydrophilic and
hydrophobic substrates. In case of water-soluble water-soluble substrates, an
amphiphilic thiol was also needed.
A. Postigo, S. Kopsov, C. Ferreri, C. Chatgilialoglu, Org. Lett., 2007,
9, 5159-5162.