Protocol | Published:

Use of Raman spectroscopy as a tool for in situ monitoring of microwave-promoted reactions

Nature Protocols volume 3, pages 17 (2008) | Download Citation

Subjects

Abstract

The progress of microwave-promoted reactions can be monitored by interfacing a Raman spectrometer with a scientific microwave unit. The apparatus is assembled from commercially available components. It is used in this protocol to follow the base-catalyzed reaction of salicylaldehyde with ethylacetoacetate to yield 3-acetylcoumarin. It is possible to watch the reaction spectroscopically in real time, determine when it reaches completion and thus use it as a tool for rapid reaction optimization.

Access optionsAccess options

Rent or Buy article

Get time limited or full article access on ReadCube.

from$8.99

All prices are NET prices.

References

  1. 1.

    (ed.) Microwaves in Organic Synthesis (Wiley-VCH, Weinheim, 2006).

  2. 2.

    & Microwaves in Organic and Medicinal Chemistry (Wiley-VCH, Weinhiem, 2005).

  3. 3.

    & (eds.) Microwave-assisted Organic Synthesis (Blackwell, Oxford, 2005).

  4. 4.

    Microwave Synthesis: Chemistry at the Speed of Light (CEM Publishing, Matthews, NC, 2002).

  5. 5.

    Controlled microwave heating in organic and medicinal chemistry. Angew. Chem. Int. Ed. Engl. 43, 6250–6284 (2004).

  6. 6.

    , & Microwave-accelerated homogeneous catalysis in organic chemistry. Acc. Chem. Res. 35, 717–727 (2002).

  7. 7.

    , , & Increasing rates of reaction: Microwave-assisted organic synthesis for combinatorial chemistry. J. Comb. Chem. 4, 95–105 (2002).

  8. 8.

    , & Microwave synthesis of nanoporous materials. ChemPhysChem 7, 296–319 (2006).

  9. 9.

    , & Temperature-resolved, in-situ powder X-ray diffraction of silver iodide under microwave irradiation. PhysChemComm 135–137 (2002).

  10. 10.

    & Real-time in situ Raman analysis of microwave-assisted organic reactions. Appl. Spectrosc. 58, 41–46 (2004).

  11. 11.

    & Real-time monitoring of microwave-promoted organometallic ligand-substitution reactions using in-situ Raman spectroscopy. Chem. Commun. 3615–3616 (2006).

  12. 12.

    & Real-time monitoring of microwave-promoted Suzuki coupling reactions using in situ Raman spectroscopy. Org. Lett. 8, 4588–4591 (2006).

  13. 13.

    , & Using in situ Raman monitoring as a tool for rapid optimisation and scale-up of microwave-promoted organic synthesis: esterification as an example. Org. Biomol. Chem. 5, 822–825 (2007).

  14. 14.

    & In-situ Raman spectroscopy as a probe for the effect of power on microwave-promoted Suzuki coupling reactions. Org. Biomol. Chem. 5, 2770–2775 (2007).

  15. 15.

    & Lin C.H. & Sun, C.M. Recent advances in coumarins and 1-azacoumarins as versatile biodynamic agents. Curr. Med. Chem. 13, 2795–2818 (2006).

  16. 16.

    & Challenges and opportunities in drug discovery from plants. Curr. Sci. 92, 1251–1257 (2007).

  17. 17.

    Challenges and opportunities in drug discovery from plants. Curr. HIV Res. 4, 347–363 (2006).

  18. 18.

    , , & Natural and synthetic coumarin derivatives with anti-inflammatory/antioxidant activities. Curr. Pharm. Des. 10, 3813–3833 (2004).

  19. 19.

    , & Pyrans and benzo derivatives: synthesis. In Comprehensive Heterocyclic Chemistry II Vol. 5 (eds. Katritzky, A.R., Rees, C.W., Scriven, E.F.V. & McKillop, A.) 1–55 (Pergamon, Oxford, 1996).

  20. 20.

    , & Use of microwave irradiation and solid acid catalysts in an enhanced and environmentally friendly synthesis of coumarin derivatives. Synlett 608–610 (1999).

  21. 21.

    , & Microwave acceleration of the Pechmann reaction on graphite/montmorillonite K10: application to the preparation of 4-substituted 7-aminocoumarins. Tetrahedron Lett. 42, 2791–2794 (2001).

  22. 22.

    , , , & Efficient green procedure for the synthesis of coumarin derivatives by a one-pot, three-component reaction under Solvent Free conditions. Synth. Commun. 37, 183–189 (2007).

  23. 23.

    , , , , & Dipyridine copper chloride catalyzed coumarin synthesis via Pechmann condensation under conventional heating and microwave irradiation. ARKIVOC 23–27 (2006).

  24. 24.

    Microwave accelerated preparation of [bmim][HSO4] ionic liquid: an acid catalyst for improved synthesis of coumarins. Molecules 8, 541–555 (2003).

  25. 25.

    Coumarins: Fast synthesis by Knoevenagel condensation under microwave irradiation. J. Chem. Res. 468–469 (1998).

Download references

Acknowledgements

We thank the University of Connecticut for research funding. We acknowledge technical support from CEM Corporation (in particular T. Michael Barnard) and Enwave Optronics (in particular Eric Wu and Kevin Pan).

Author information

Affiliations

  1. Department of Chemistry, University of Connecticut, 55 North Eagleville Road, Storrs, Connecticut 06269-3060, USA.

    • Nicholas E Leadbeater
    •  & Jason R Schmink

Authors

  1. Search for Nicholas E Leadbeater in:

  2. Search for Jason R Schmink in:

Corresponding author

Correspondence to Nicholas E Leadbeater.

About this article

Publication history

Published

DOI

https://doi.org/10.1038/nprot.2007.453

Further reading

Comments

By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.