A mild and selective deoximation method using γ-picolinium chlorochromate (γ-PCC)

Article abstract of DOI:10.1081/SCC-120003618

A mild and efficient method for the oxidative conversion of oximes to their parent carbonyl compounds with γ-picolinium chlorochromate (γ-PCC) under non-aqueous conditions is described.

Full text of DOI:10.1081/SCC-120003618

This article was downloaded by: [University of Leeds]
On: 10 December 2014, At: 10:02
Publisher: Taylor & Francis
Informa Ltd Registered in England and Wales Registered Number: 1072954 Registered office: Mortimer House,
37-41 Mortimer Street, London W1T 3JH, UK
Synthetic Communications: An International Journal
for Rapid Communication of Synthetic Organic
Chemistry
Publication details, including instructions for authors and subscription information:
http://www.tandfonline.com/loi/lsyc20
A MILD AND SELECTIVE DEOXIMATION METHOD USING γ-
PICOLINIUM CHLOROCHROMATE (γ-PCC)
P. Salehi a , M. M. Khodaei b & M. Goodarzi b
a Department of Phytochemistry , Medicinal Plants Research Institute , Shahid Beheshti
University , Evin, Tehran, 1983963113, Iran
b Department of Chemistry , Razi University , Kermanshah, Iran
Published online: 16 Aug 2006.
To cite this article: P. Salehi , M. M. Khodaei & M. Goodarzi (2002) A MILD AND SELECTIVE DEOXIMATION METHOD USING γ-
PICOLINIUM CHLOROCHROMATE (γ-PCC), Synthetic Communications: An International Journal for Rapid Communication of
Synthetic Organic Chemistry, 32:8, 1259-1263, DOI: 10.1081/SCC-120003618
To link to this article: http://dx.doi.org/10.1081/SCC-120003618
PLEASE SCROLL DOWN FOR ARTICLE
Taylor & Francis makes every effort to ensure the accuracy of all the information (the “Content”) contained
in the publications on our platform. However, Taylor & Francis, our agents, and our licensors make no
representations or warranties whatsoever as to the accuracy, completeness, or suitability for any purpose of the
Content. Any opinions and views expressed in this publication are the opinions and views of the authors, and
are not the views of or endorsed by Taylor & Francis. The accuracy of the Content should not be relied upon and
should be independently verified with primary sources of information. Taylor and Francis shall not be liable for
any losses, actions, claims, proceedings, demands, costs, expenses, damages, and other liabilities whatsoever
or howsoever caused arising directly or indirectly in connection with, in relation to or arising out of the use of
the Content.
This article may be used for research, teaching, and private study purposes. Any substantial or systematic
reproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any
form to anyone is expressly forbidden. Terms & Conditions of access and use can be found at http://
www.tandfonline.com/page/terms-and-conditions

SYNTHETIC COMMUNICATIONS, 32(8), 1259–1263 (2002)
A MILD AND SELECTIVE DEOXIMATION
METHOD USING c-PICOLINIUM
CHLOROCHROMATE (c-PCC)
2
P. Salehi,1, M. M. Khodaei,2, andM. Goodarzi
*
*
1Department of Phytochemistry, Medicinal Plants
Research Institute, Shahid Beheshti University,
Evin, Tehran 1983963113, Iran
2Department of Chemistry, Razi University,
Kermanshah, Iran
ABSTRACT
A mild and efficient method for the oxidative conversion of
oximes to their parent carbonyl compounds with g-picolinium
chlorochromate (g-PCC) under non-aqueous conditions is
described.
Oximes are useful intermediates in organic chemistry and are utilized
for purification and characterization of aldehydes and ketones. They are
also used as protecting groups for carbonyl compounds.1 An alternative
pathway to aldehydes and ketones is the synthesis of aldoximes and ketox-
imes from non-carbonyl substrates.2 Therefore regeneration of carbonyl
compounds from their oximes has received much attention.3–15 Some
chlorochromate derivatives are also used for this purpose,16–21 but they
*Corresponding authors.
1259
Copyright & 2002 by Marcel Dekker, Inc.
www.dekker.com

1260
SALEHI, KHODAEI, AND GOODARZI
suffer from low yield of product, inefficiency of the reagent and vigorous
reaction conditions.
Very recently we introduced g-picolinium chlorochromate (g-PCC)
as an efficient reagent for the oxidation of alcohols under non-
aqueous conditions,22 and now its application as a convenient, mild and
efficient reagent for the oxidative cleavage of oximes to carbonyl compounds
is reported.
In all of the reactions the mixture of oximes and g-PCC were stirred in
dichloromethane at room temperature to give the corresponding aldehydes
and ketones in good to excellent yields (scheme, table). Aromatic aldoximes
(Entries 1,2) as well as aromatic ketoximes (Entries 5–8) were oxidized to
parent carbonyl compounds. Cyclic (Entries 9–11) and acyclic (Entries 4,12)
aliphatic aldoximes and ketoximes were also cleaved at carbon–nitrogen
double bond successfully. Acid sensitive methoxy groups (Entry 2) remained
intact and a,b-unsaturated, cinnamaldoxime (Entry 3) was deoximated
without any difficulty. It must be noted that the overoxidation of aldehydes
was not observed.
Scheme.
In all of the reactions 1.5 molar equivalents of the oxidant were
consumed, which shows the efficiency of the reagent and the advantage of
g-PCC in comparison with other chlorochromate derivatives. In contrast,
deoximation with pyridinium chlorochromate suffers from long reaction
times and low yields.23 The overoxidation products are usually observed
when the above reaction is carried out in the presence of hydrogen peroxide.24
Mildness of the reaction condition, ease of work-up procedure, stabil-
ity and efficiency of the reagent and high yields of products are among the
outstanding advantages of this new method.
EXPERIMENTAL
All of the products are known compounds and were identified by
1
comparison of their spectral data (IR, H NMR) and physical properties

DEOXIMATION METHOD USING c-PCC
1261
Table. Oxidative Cleavage of Carbon–Nitrogen Double Bonds with
g-PCC at Room Temperature
Time
(h)
Yield
(%)
Entry
1
Substrate
Product
13
85
2
980
3
4
10
4
90
9
5
3
5
6
9
6
7
13
79
95
4.5
8
9
4
15
13
9
5
75
79
10
11
12
17
10
85
77

1262
SALEHI, KHODAEI, AND GOODARZI
with those of authentic samples. Reaction monitoring was accomplished by
thin layer chromatography on silica gel polygram SIL G/UV 254 plates. All
yields refer to isolated products.
General Procedure for the Regeneration of Carbonyl Compounds
from Oximes with c-PCC
To a solution of oxime (1 mmol) in dichloromethane (5 ml) g-pico-
linium chlorochromate (1.5 mmol) was added. The mixture was stirred mag-
netically until complete consumption of substrate. The progress of the
reaction was followed by thin layer chromatography on silica gel
(CCl4/Ether: 4/1). Hydrochloric acid (20%, 10 ml) was added and the
mixture extracted with ether (3 Â 15 ml). The combined extracts were
dried (MgSO4) and concentrated. The carbonyl compounds were isolated
in 75–95% yields.
ACKNOWLEDGMENT
We are grateful to Razi University Research Council for financial
support of this work.
REFERENCES
1. Green, T.W.; Wuts, P.G. Protective Groups in Organic Synthesis, 2nd
Ed.; Wiley: New York, 1991; p. 214.
2. Mukai, C.; Hanaoka, M. Synlett 1996, 11.
3. Donaldson, R.; Sadler, J.C.; Boyrn, S.; Nckenzie, A.T.; Fuchs, P.L.
J. Org. Chem. 1983, 48, 2167.
4. Firouzabadi, H.; Iranpoor, N.; Kiaeezadeh, F.; Toofan, J. Tetrahedron
1986, 42, 719.
5. Shim, S.B.; Kim, K.; Kim, Y.H. Tetrahedron Lett. 1987, 28, 719.
6. Firouzabadi, H.; Mottaghinejad, E.; Seddighi, M. Synth. Commun.
1989, 19, 645.
7. Lee, J.G.; Kwak, K.H.; Hwang, J.P. Synth. Commun. 1992, 22, 2435.
8. Tamami, B.; Goudarzian, N. Eur. Polym. J. 1992, 28, 1035.
9. Wall, A.; Ganeshpure, P.A.; Satish, S. Bull. Chem. Soc. Jpn. 1993, 66,
1847.
10. Singh, L.; Kam, R.N. Synth. Commun. 1993, 23, 3139.

DEOXIMATION METHOD USING c-PCC
1263
11. Firouzabadi, H.; Mohammadpoor-Baltork, I. Synth. Commun. 1994,
24, 489.
12. Barhate, N.B.; Gajare, A.S.; Wakharker, R.D.; Sudalai, A.
Tetrahedron Lett. 1997, 38, 653.
13. Chaudhari, S.S.; Akamanchi, K.G. Synthesis 1999, 760.
14. Mohammadpoor-Baltork, I.; Hajipour, A.R.; Haddadi, R. J. Chem.
Res. (S) 1999, 102.
15. Mukai, C.; Nomura, I.; Kataoka, O.; Hanaoka, M. Synthesis 1999, 1872.
16. Zhang, G.S.; Yang, D.H.; Chen, M.F. Synth. Commun. 1998, 28,
3721.
17. Zhang, G.S.; Yang, D.H.; Chen, M.F.; Cai, K. Synth. Commun. 1998,
28, 607.
18. Rao, C.G.; Radhakrishnan, A.H.; Singh, B.B.; Bhatnagar, S.P.
Synthesis 1983, 808.
19. Zhang, G.S.; Yang, D.H.; Chen, M.F.; Cai, K. Synth. Commun. 1998,
28, 2221.
20. Mohammadpoor-Baltork, I.; Pouranshirvani, S. Synth. Commun.
1996, 26, 1.
21. Zhang, G.S.; Chai, B. Synth. Commun. 2000, 30, 1849 .
22. Khodaie, M.M.; Salehi, P.; Goodarzi, M. Synth. Commun. 2001, 31(8),
In press.
23. Maloney, J.R.; Lyle, R.E.; Saavedra, J.E.; Lyle, G.G. Synthesis
1978, 212.
24. Drabowicz, J. Synthesis 1980, 125.
Received in the UK February 8, 2001