Enhancing selectivity in oxidation catalysis with sol-gel nanocomposites

Organic and Biomolecular Chemistry

Volumn 3, Issue 13, 2005, Pages 2389-2392

  Gancitano, Pamela ^a   Ciriminna, Rosaria ^a   Testa, Maria Luisa ^a   Fidalgo, Alexandra ^b   Ilharco, Laura M ^b   Pagliaro, Mario ^b  

^a CNR   (Italy)

^b INSTITUTO SUPERIOR TÉCNICO   (Portugal)

Author keywords

[No Author keywords available]

Indexed keywords

ACETONITRILE; CATALYSIS; HYDROPHOBICITY; HYDROXYLATION; KETONES; NANOSTRUCTURED MATERIALS; OLEFINS; ORGANIC ACIDS; OXIDATION; POROUS MATERIALS; SOL-GELS; SYNTHESIS (CHEMICAL);

Α-HYDROXY ACIDS; NANOCOMPOSITES; ORGANOCATALYSTS; SILICA MATRIX;

CATALYST SELECTIVITY;

EID: 22744440342     PISSN: 14770520     EISSN: None     Source Type: Journal    
DOI: 10.1039/b505949f     Document Type: Review

References (31)

1. For an advanced account, see: D. Avnir, L. C. Klein, D. Levy, U. Schubert and A. B. Wojcik, Organo-silica Sol-Gel Materials, in The Chemistry of Organosilicon Compounds 2, ed. Z. Rappoport and Y. Apeloig, Wiley, London, 1998; ch. 40, pp. 2317-2362.
2. While rendering the resulting conversion atom-efficient. For a recent discussion of this central topic of modern synthetic chemistry, see D. J. Cole-Hamilton, Science, 2003, 299, 1702.
3. The wide scope and importance of sol-gel doped catalysts to modern organic synthesis was recently reviewed in: R. Ciriminna and M. Pagliaro, Curr. Org. Chem., 2004, 18, 1851.
4. Functionalized silica gels are commercial reagents with a rapidly growing market. Doped silica gels offer several technical advantages over well known organic resins being solvent-independent (rigid porous structure and no swelling) and with a high density of functional groups (small volume of gel required). Silica works in all solvents (organic and aqueous), is easy to weigh and handle, mechanically stable and suitable for scale-up. Sigma-Aldrich, for instance, commercializes the silica gels produced by SiliCycle Inc. See also the URL: www.silicycle.com.
5. (a) S. Campestrini, M. Carraro, U. Tonellato, M. Pagliaro and R. Ciriminna, Tetrahedron Lett., 2004, 45, 7283;
6. (b) R. Ciriminna and M. Pagliaro, Chem. Eur. J., 2003, 9, 5067;
7. (c) R. Ciriminna, S. Campestrini and M. Pagliaro, Adv. Synth. Catal., 2003, 345, 1261;
8. (d) R. Ciriminna, J. Blum, D. Avnir and M. Pagliaro, Chem. Commun., 2000, 1441.
9. D. Avnir, Acc. Chem. Res., 1995, 28, 328.
10. (a) K. C. Nicolau, W. M. Dai and R. K. Kuy, Angew. Chem., Int. Ed. Engl, 1994, 33, 15;
11. (b) S. Shinagawa, T. Kanamaru, S. Harada, M. Asai and H. Ookazaki, J. Med. Chem., 1987, 30, 1458.
12. The industrial synthesis starts from cyanohydrins. Catalytic routes, more limited in scope, have also been developed based on supported metal catalysts: (a) M. Rossi, L. Prati in Green Chemistry: Challenging perspectives, ed. P. Tundo, P. T. Anastas, Oxford University Press, Oxford, 2000, p. 183;
13. or enzymes: (b) C. H. Wong and J. R. Matos, J. Org. Chem., 1985, 50, 1992 and since 2002 the US company Diversa has commercialized the enzyme nitrilase for the biocatalytic synthesis of α-hydroxy acids.
14. (a) T. K. M. Shing, E. K. W. Tam, V. W.-F. Tai, I. H. F. Chung and Q. Jiang, Chem. Eur. J., 1996, 2, 50;
15. the method has been recently improved with a significant (one seventh) reduction in the amount of catalytic Ru; (b) B. Plietker and M. Niggemann, Org. Lett., 2003, 5, 3353.
16. (a) A. E. J. de Nooy, A. Besemer and H. van Bekkum, Tetrahedron, 1995, 51, 8023;
17. (b) TEMPO-mediated oxidations of alcohols are now commercial. The chemical manufacturer DSM, for instance, uses an oxidation process analogous to that described in R. Ben-Daniel, P. Alsters and R. Neumann, J. Org. Chem., 2001, 66, 8650;
18. (c) For a thorough discussion on the oxidation chemistry of TEMPO, see A. E. J. de Nooy, A. C. Besemer and H. van Bekkum, Synthesis, 1996, 1153.
19. -, as shown in: A. Besemer, PhD Thesis, Delft University of Technology, 1994.
20. -1.
21. M. L. Testa, R. Ciriminna, C. Hajji, E. Zaballos-Oarcia, M. Ciclosi, J. Sepúlveda-Arques and M. Pagliaro, Adv. Synth. Catal., 2004, 346, 655.
22. The first use of these ORMOSILS in the oxidation of alcohols is reported in: R. Ciriminna, C. Bolm, T. Fey and M. Pagliaro, Adv. Synth. Catal., 2002, 344, 159.
23. P. Seneci, Solid-Phase Synthesis and Combinatorial Technologies, John Wiley and Sons, New York, 2000.
24. M. D. Jones, R. Raja, J. M. Thomas, B. F. G. Johnson, D. W. Lewis, J. Rouzaud and K. D. M. Harris, Angew. Chem. Int. Ed., 2003, 42, 4326.
25. T. Fey, H. Fischer, S. Bachmann, K. Albert and C. Bolm, J. Org. Chem., 2001, 66, 8154.
26. A. Fidalgo and L. M. Ilharco, Chem. Eur. J., 2004, 10, 315.
27. R. Criminna, L. M. Ilharco, A. Fidalgo, S. Campestrini, M. Pagliaro, Soft Matter, (submitted).
28. For instance, also in the case of catalytic processes mediated by entrapped precious metals, see 5b, or by enzymes see: M. T. Reetz, P. Tielmann, W. Wiesenhofer, W. Konen and A. Zonta, Adv. Synth. Catal., 2003, 345, 717.
29. S. Hayakawa and L. L. Herch, J. Non-Cryst. Solids, 1998, 242, 131.
30. -1: a requirement clearly met by sol-gel entrapment of 4-oxo-TEMPO. W. Kesber, personal communication, (prices as of March 23, 2005);
31. M. Pagliaro, D. Avnir, J. Blum, G. Deganello, US Pat. 6797773 B1, 2004.