Paper
RSC Advances
¨
3 J. E. Backvall, Modern Oxidation Methods, Wiley, 2011.
4 J. C. Elliott, Structure and chemistry of the apatites and other
calcium orthophosphates, Elsevier, 2013.
5 M. Jarcho, Clin. Orthop. Relat. Res., 1981, 157, 259–278.
6 B. Locardi, U. Pazzaglia, C. Gabbi and B. Prolo,
Biomaterials, 1993, 14, 437–441.
´
7 M. Domınguez, F. Romero-Sarria, M. Centeno and
J. Odriozola, Appl. Catal., B, 2009, 87, 245–251.
8 M. P. Reddy, A. Venugopal and M. Subrahmanyam, Water
Res., 2007, 41, 379–386.
9 K. De Groot, Biomaterials, 1980, 1, 47–50.
10 P. Layrolle, A. Ito and T. Tateishi, J. Am. Ceram. Soc., 1998, 81,
1421–1428.
Fig. 6 Reusability of the catalyst for oxidation of diphenylmethanol by
Co–NHAp.
11 J. Kagan, P. Y. Juang, B. E. Firth, J. T. Przybytek and
S. P. Singh, Tetrahedron Lett., 1977, 18, 4289–4290.
12 J. Delaunay, A. Lebouc, A. Tallec and J. Simonet, J. Chem.
Soc., Chem. Commun., 1982, 387–388, DOI: 10.1039/
c39820000387.
13 H. Monma and T. Kamiya, J. Mater. Sci., 1987, 22, 4247–4250.
14 L. Lopez and L. Troisi, Tetrahedron Lett., 1989, 30, 3097–
3100.
group of alcohols or from the benzylic position of alkyl arenes
by superoxocobalt(III),44,68–70 as shown in Scheme 3.
Finally, recyclability of catalyst was investigated. For this
purpose, catalyst was separated aer completion of oxidation
reaction and was washed with ethanol, dried in oven and it was
reused for ve times without any signicant decrease in its
activity and selectivity (Fig. 6).
15 S. V. Dorozhkin and M. Epple, Angew. Chem., Int. Ed. Engl.,
2002, 41, 3130–3146.
16 S. Bose and S. K. Saha, Chem. Mater., 2003, 15, 4464–4469.
17 A. L. Gavrilova, C. J. Qin, R. D. Sommer, A. L. Rheingold and
B. Bosnich, J. Am. Ceram. Soc., 2002, 124, 1714–1722.
4. Conclusions
In conclusion, we have reported the application of Co–NHAp as
an effective catalyst for selective aerobic oxidation of alkyl are-
nes and alcohols to their corresponding carbonyl compounds. It
was found that this catalysis system is highly efficient and
selective for the oxidation of various secondary benzylic C–H
bond. It is worth mentioning that oxidation of toluene,
a primary benzylic C–H bond, did not take place. Further, it is
more efficient for the oxidation of secondary benzylic alcohols
and less efficient for aliphatic primary and secondary alcohols.
To the best of our knowledge, this novel heterogeneous catalyst
has not been reported previously for aerobic catalytic oxidations
of alkyl arenes and alcohols. Advantages of this heterogeneous
catalyst are using NHAp as a natural support, air as a green
oxidant, simple procedures, high efficiency and excellent
reusability.
´
18 L. I. Simandi, Catalytic Activation of Dioxygen by Metal
Complexes, Springer, Netherlands, 2012.
19 D. H. R. Barton, A. E. Martell and D. T. Sawyer, The Activation
of Dioxygen and Homogeneous Catalytic Oxidation, Springer,
US, 2012.
20 J. J. Bozell, B. R. Hames and D. R. Dimmel, J. Org. Chem.,
1995, 60, 2398–2404.
21 G. T. Musie, M. Wei, B. Subramaniam and D. H. Busch,
Inorg. Chem., 2001, 40, 3336–3341.
22 X. Hu, Z. Huang, G. Gu, L. Wang and B. Chen, J. Mol. Catal. A:
Chem., 1998, 132, 171–179.
23 D. R. Larkin, J. Org. Chem., 1990, 55, 1563–1568.
24 B. Bhatia and J. Iqbal, Tetrahedron Lett., 1992, 33, 7961–7964.
25 R. Giannandrea, P. Mastrorilli, C. Nobile and G. Suranna, J.
Mol. Catal., 1994, 94, 27–36.
26 A. E. Shilov and G. B. Shul'pin, Chem. Rev., 1997, 97, 2879–
2932.
27 B. B. Wentzel, M. P. Donners, P. L. Alsters, M. C. Feiters and
R. J. Nolte, Tetrahedron, 2000, 56, 7797–7803.
28 M. M. Dell'Anna, P. Mastrorilli and C. F. Nobile, J. Mol. Catal.
A: Chem., 1996, 108, 57–62.
Acknowledgements
We gratefully acknowledge nancial support of the Iran
National Elites Foundation (INEF) and the Research Council of
Shahid Beheshti University.
29 M. M. Dell'Anna, P. Mastrorilli, C. F. Nobile and L. Lopez, J.
Mol. Catal. A: Chem., 1996, 111, 33–36.
Notes and references
1 R. A. Sheldon and J. K. Kochi, Metal-catalyzed oxidations of 30 S. L. Jain and B. Sain, Angew. Chem., Int. Ed. Engl., 2003, 42,
organic compounds: mechanistic principles and synthetic
1265–1267.
methodology including biochemical processes, Academic 31 V. B. Sharma, S. L. Jain and B. Sain, J. Mol. Catal. A: Chem.,
Press, 1981. 2004, 212, 55–59.
2 A. R. Katritzky and R. J. K. Taylor, Comprehensive Organic 32 F. Rajabi and B. Karimi, J. Mol. Catal. A: Chem., 2005, 232,
Functional Group Transformations II: Comprehensive 95–99.
A
Review of the Synthetic Literature 1995–2003, Elsevier 33 S. Jain and O. Reiser, ChemSusChem, 2008, 1, 534–541.
Science, 2004.
This journal is © The Royal Society of Chemistry 2016
RSC Adv., 2016, 6, 48396–48404 | 48403