N-Chlorosuccinimide (NCS)
N-Chlorosuccinimide (NCS) is a chlorinating and oxidizing agent that is used as source for chlorine in radical reactions and various electrophilic additions.
Recent Literature
N-Halosuccinimides are efficiently activated in
trifluoromethanesulfonic acid and BF3-H2O, allowing
the halogenations of deactivated aromatics. BF3-H2O is
more economic, easy to prepare, nonoxidizing, and offers sufficiently high
acidity.
G. K. S. Prakash, T. Mathew, D. Hoole, P. M. Esteves, Q. Wang, G. Rasul, G.
A. Olah, J. Am. Chem. Soc.,
2004,
126, 15570-15776.
A mild, efficient, Cu(I)-catalyzed method for the synthesis of aryl chlorides
from arylboronic acids is particularly useful for the conversion of
electron-deficient arylboronic acids to aryl chlorides, a transformation that is
inefficient in the absence of Cu catalysis.
H. Wu, J. Hynes, Jr., Org. Lett., 2010,
12, 1192-1195.
A mild palladium-catalyzed, regioselective chlorination, bromination, and
iodination of arene C-H bonds using N-halosuccinimides as oxidants is
described. These transformations can provide products that are complementary
to those obtained via conventional electrophilic aromatic substitution
reactions.
D. Kalyani, A. R. Dick, W. Q. Anani, M. S. Sanford, Org. Lett.,
2006,
8, 2523-2526.
Using triethylamine as catalyst in Hunsdiecker reactions with N-halosuccinimides
as Br+ or I+ source, cinnamic acids, and propiolic acids are
converted to the corresponding α-halostyrenes and 1-halo-1-alkynes in good isolated yields within 1-5 min.
J. Prakash, S. Roy, J. Org. Chem.,
2002, 67, 7861-7864.
An intramolecular chloroamination of allenes with N-chlorosuccinimide
proceeds under mild conditions in the presence of a 1,10-phenanthroline-ligated
cationic silver complex and 2,6-lutidine as a base. The reaction tolerates
various functional groups. The chloroamination products are useful synthetic
intermediates and can be easily transformed into functionalized 3-pyrroline and
pyrrole derivatives.
M. Sai, S. Matsubara, Org. Lett., 2011,
13, 4676-4679.
Various 2-aryl-3-arylamino-2-alkenenitriles give N-arylindole-3-carbonitriles
in a one-pot manner through NBS- or NCS-mediated halogenation followed by
Zn(OAc)2-catalyzed intramolecular cyclization. The process involves
the formation of arylnitrenium ion intermediates, which undergo an electrophilic
aromatic substitution to give the cyclized N-arylindoles.
Q. Yan, J. Luo, D. Zhang-Negrerie, H. Li, X. Qi, K. Zhao, J. Org. Chem., 2011,
76, 8690-8697.
A divergent and regioselective synthesis of either 3-substituted benzisoxazoles
or 2-substituted benzoxazoles from readily accessible ortho-hydroxyaryl
N-H ketimines proceeds in two distinct pathways through a common N-Cl imine
intermediate: (a) N-O bond formation to form benzisoxazole under anhydrous
conditions and (b) NaOCl mediated Beckmann-type rearrangement to form
benzoxazole, respectively.
C.-y Chen, T. Andreani, H. Li, Org. Lett., 2011,
13, 6300-6303.
A fluorous (S)-pyrrolidine-thiourea bifunctional organocatalyst shows
good activity and enantioselectivity for direct α-chlorination of aldehydes
using N-chlorosuccinimide (NCS) as the chlorine source. The catalyst can
be recovered from the reaction mixture by fluorous solid-phase extraction with
excellent purity for direct reuse.
L. Wang, C. Cai, D. P. Curran, W. Zhang, Synlett, 2010, 433-436.
A direct organocatalytic enantioselective α-chlorination of aldehydes
proceeds for a series of different aldehydes with NCS as the chlorine source
using easily available catalysts such as L-proline amide and (2R,5R)-diphenylpyrrolidine.
The α-chloro aldehydes are obtained in very good yield and high
enantioselectivity.
N. Halland, A. Braunton, S. Bachmann, M. Marigo, K. A. Jorgensen, J. Am. Chem. Soc.,
2004,
126, 4790-4791.
A smooth oxidation of several thiol derivatives by a combination of N-chlorosuccinimide
and dilute hydrochloric acid afforded the corresponding sulfonyl chlorides in
good yield.
A. Nishiguchi, K. Maeda, S. Miki,
Synthesis, 2006, 4131-4134.
In situ preparation of sulfonyl chlorides from thiols by oxidation with N-chlorosuccinimide
(NCS), tetrabutylammonium chloride, and water followed by reaction with amine or
sodium azide in the same reaction vessel enables a convenient synthesis of
sulfonamides and sulfonyl azides.
H. Veisi, R. Ghorbani-Vaghei, S. Hemmati, J. Mahmoodi, Synlett, 2011,
2315-2320.
