Skip to main content
SpringerLink
Log in

Immobilizing a single pybox ligand onto a library of solid supports

  • Published:
Molecular Diversity Aims and scope Submit manuscript

Abstract

Chiral pyridinebis(oxazoline) (pybox) ligands can be efficiently immobilized onto silica through position 4 of the pyridine ring. The crucial intermediate in this strategy is 4-chloropybox, which is prepared in good yield from chelidamic acid. 4-Chloropybox reacts with p-hydroxybenzaldehyde and p-aminophenol to give two intermediates (pybox-CHO and pybox-NH2) that allow to introduce the formyl and amino groups able to link to spacers with triethoxysilylgroups. The modified ligands and their ruthenium complexes are immobilized by grafting onto pre-formed silicas or, alternatively, the support is created by sol-gel synthesis using the functionalizedchiral ligand as a silica monomer. In this way it is possible to create a library where the variation involves the support rather than the catalyst. The aim of this approach is to study the influence of different parameters, such as the textural properties of the support and the immobilization method, on the functionalization and catalytic performance. Some of the immobilized complexes are compared as heterogeneous catalysts in the cyclopropanation reaction of styrene with ethyl diazoacetate.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

References

  1. Blaser, H.-U., Enantioselective catalysis in fine chemicals production, Chem. Commun., (2003) 293–296.

  2. De Vos, D. E., Vankelecom, I. F. J. and Jacobs, P. A. (eds.), Chiral Catalysts Immobilization and Recycling, Wiley-VCH, Weinheim, 2000.

    Google Scholar 

  3. Altava, B., Burguete, M. I., Fraile, J. M., García, J. I., Luis S. V., Mayoral, J. A. and Vicent, M. J., How important is the inert matrix of supported enantiomeric catalysts? Reversal of topicity with two polystyrene backbones, Angew. Chem. Int. Ed., 39 (2000) 1503–1506.

    Article  CAS  Google Scholar 

  4. Rechavi, D. and Lemaire, M., Enantioselective catalysts using heterogeneous bis(oxazoline) ligands: which factors influence the enantioselectivity?, Chem. Rev., 102 (2002) 3467–3494.

    Article  CAS  Google Scholar 

  5. Fraile, J. M., García, J. I., Mayoral, J. A., Tarnai, T. and Harmer, M. A., Bis(oxazoline)-copper complexes, supported by electrostatic interactions, as heterogeneous catalysts for enantioselective cyclopropanation reactions: influence of the anionic support, J. Catal., 186 (1999) 214–221.

    Article  CAS  Google Scholar 

  6. Fernández, A. I., Fraile, J. M., García, J. I., Herrerías, C. I., Mayoral, J. A. and Salvatella, L., Reversal of enantioselectivity by change of solvent with clay-immobilized bis(oxazoline)-copper catalysts, Catal. Commun., 2 (2001) 165–170.

    Article  Google Scholar 

  7. Fraile, J. M., García, J. I., Harmer, M. A., Herrerías, C. I., Mayoral, J. A., Reiser, O. and Werner, H., Immobilisation of bis(oxazoline)-copper complexes on clays and nanocomposites. Influence of different parameters on activity and selectivity, J. Mater. Chem., 12 (2002) 3290–3295.

    Article  CAS  Google Scholar 

  8. Burguete, M. I., Fraile, J. M., García, J. I., García-Verdugo, E., Luis, S. V. and Mayoral, J. A., Polymer-supported bis(oxazoline)-copper complexes as catalysts in cyclopropanation reactions, Org. Lett., 2 (2000) 3905–3908.

    Article  CAS  Google Scholar 

  9. Burguete, M. I., Fraile, J. M., García, J. I., García-Verdugo, E., Herrerías, C. I., Luis, S. V. and Mayoral, J. A., Bis(oxazoline)-copper complexes covalently bonded to insoluble support as catalysts in cyclopropanation reactions, J. Org. Chem., 66 (2001) 8893–8901.

    Article  CAS  Google Scholar 

  10. Orlandi, S., Mandoli, A., Pini, D. and Salvadori, P., An insoluble polymer-bound bis-oxazoline copper(II) complex: a highly efficient heterogeneous catalyst for the enantioselective Mukaiyama aldol reaction, Angew. Chem. Int. Ed., 40 (2001) 2519–2521.

    Article  CAS  Google Scholar 

  11. Hallman, K. and Moberg, C., Polymer-bound bis(oxazoline) as a chiral catalyst, Tetrahedron: Asymmetry, 12 (2001) 1475–1478.

    Article  CAS  Google Scholar 

  12. Rechavi, D. and Lemaire, M., Heterogenization of a chiral bis(oxazoline) catalyst by grafting onto silica, Org. Lett., 3 (2001) 2493–2496.

    Article  CAS  Google Scholar 

  13. Corma, A., García, H., Moussaif, A., Sabater, M. J., Zniber, R. and Redouane, A., Chiral copper(II) bisoxazoline covalently anchored to silica and mesoporous MCM-41 as a heterogeneous catalyst for the enantioselective Friedel-Crafts hydroxyalkylation, Chem. Commun., (2002) 1058–1059.

  14. Nishiyama, H., Itoh, Y., Sugawara, Y., Matsumoto, H., Aoki, K. and Itoh, K., Chiral ruthenium(II)-bis(2-oxazolin-2-yl)pyridine complexes. Asymmetric catalytic cyclopropanation of olefins and diazoacetates, Bull. Chem. Soc. Jpn., 68 (1995) 1247–1262.

    Article  CAS  Google Scholar 

  15. Nishiyama, H., Yamaguchi, S., Kondo, M. and Itoh, K., Electronic substituent effect of nitrogen ligand in catalytic asymmetric hydrosilylation of ketones: chiral 4-substituted bis(oxazolinyl)pyridines, J. Org. Chem., 57 (1992) 4306–4309.

    Article  CAS  Google Scholar 

  16. Evans, D. A., Kozlowski, M. C., Murry, J. A., Burgey, C. S., Campos, K. R., Connel, B. N. and Staples, R. J., C 2 -symmetric copper(II) complexes as chiral Lewis acids. Scope and mechanism of catalytic enantioselective aldol additions of enolsilanes to (benzyloxy)acetaldehyde, J. Am. Chem. Soc., 121 (1999) 669–685.

    Article  CAS  Google Scholar 

  17. Schaus, S. E. and Jacobsen, E. N., Asymmetric ring opening of meso epoxides with TMSCN catalyzed by (pybox)lanthanide complexes, Org. Lett., 2 (2000) 1001–1004.

    Article  CAS  Google Scholar 

  18. Iwasa, S., Maeda, H., Nishiyama, K., Tsushima, S., Tsukamoto, Y. and Nishiyama, H., A highly enantioselective 1,3-dipolar cycloaddition reaction in alcoholic media: Ni(II)-pybox-tipsom catalyst, Tetrahedron, 58 (2002) 8281–8287.

    Article  CAS  Google Scholar 

  19. Cornejo, A., Fraile, J. M., García, J. I., Gil, M. J., Legarreta, G., Luis, S. V., Martínez-Merino, V. and Mayoral, J. A., The first immobilization of pyridine-bis(oxazoline) chiral ligands, Org. Lett., 4 (2002) 3927–3930.

    Article  CAS  Google Scholar 

  20. Anderson, H., Jönsson, C. Moberg, C. and Stemme, G., Consecutive microcontact printing ligands for asymmetric catalysis in silicon channels, Sensors Actuators B 79 (2001) 78–84.

    Article  Google Scholar 

  21. Armistead, C. G., Tyler, A. J., Hambleton, F. H., Mitchell, S. A. and Hockey, J. A., The surface hydroxylation of silica, J. Phys. Chem., 73 (1969) 3947–3953.

    Article  CAS  Google Scholar 

  22. Blitz, J. P., Meverden, C. C. and Diebel III, R. E., Reactions of dibutylmagnesium with modified silica gel surfaces, Langmuir, 14 (1998) 1122–1129.

    Article  CAS  Google Scholar 

  23. Adima, A., Moreau, J. J. E. and Man, M. W. C., Chiral organic-inorganic solids as enantioselective catalytic materials, J. Mater. Chem., 7 (1997) 2331–2333.

    Article  CAS  Google Scholar 

  24. Adima, A., Moreau, J. J. E. and Man, M. W. C., Immobilization of rhodium complexes in chiral organic-inorganic hybrid materials, Chirality, 12 (2000) 411–420.

    Article  CAS  Google Scholar 

  25. Hesemann, P. and Moreau, J. J. E., Novel silica-based hybrid materials incorporating binaphthyl units: a chiral matrix effect in heterogeneous asymmetric catalysis, Tetrahedron: Asymmetry, 11 (2000) 2183–2194.

    Article  CAS  Google Scholar 

  26. Bied, C., Gauthier, D., Moreau, J. J. E. and Man, M. W. C., Preparation and characterization of new templated hybrid materials containing a chiral diamine ligand, J. Sol-Gel Sci. Tech., 20 (2001) 313–320.

    Article  CAS  Google Scholar 

  27. Macquarrie, D. J., Jackson, D. B., Mdoe, J. E. G. and Clark, J. H., Organomodified hexagonal mesoporous silicates, New J. Chem., 23 (1999) 539–544.

    Article  CAS  Google Scholar 

  28. Tanev, P. T. and Pinnavaia, T. J., Mesoporous silica molecular sieves prepared by ionic and neutral surfactant templating: a comparison of physical properties, Chem. Mater., 8 (1996) 2068–2079.

    Article  CAS  Google Scholar 

Download references

Author information

Authors and Affiliations

  1. Dep. Química Aplicada, Universidad Pública de Navarra, E-31006, Pamplona, Spain

    Alfonso Cornejo, María J. Gil & Víctor Martínez-Merino

  2. Dep. Química Orgánica, Instituto de Ciencia de Materiales de Aragón, Universidad de Zaragoza-C.S.I.C., E-50009, Zaragoza, Spain

    José M. Fraile & José I. García

  3. Dep. Química Orgánica, Instituto de Ciencia de Materiales de Aragón, Universidad de Zaragoza-C.S.I.C., E-50009, Zaragoza, Spain

    José A. Mayoral

Authors
  1. Alfonso Cornejo
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. José M. Fraile
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. José I. García
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. María J. Gil
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Víctor Martínez-Merino
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. José A. Mayoral
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to José A. Mayoral.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Cornejo, A., Fraile, J.M., García, J.I. et al. Immobilizing a single pybox ligand onto a library of solid supports. Mol Divers 6, 93–105 (2003). https://doi.org/10.1023/B:MODI.0000006838.15630.97

Download citation

  • Issue Date:

  • DOI: https://doi.org/10.1023/B:MODI.0000006838.15630.97

Search

Navigation