Exploitation of a novel ‘on–off’ photoinduced electron-transfer (PET) sensor against conventional ‘off–on’ PET sensors†

Abstract

A novel PET sensor for sugar sensing which changes its fluorescence intensity in an ‘on–off’ manner was designed from (tetraphenylporphyrinato)tin(IV)

References

1. A. P. De Silva, H. Q. N. Gunarathe and C. P. McCoy, Chem. Commun., 1996, 2399; A. P. De Silva, H. Q. N. Gunarathe, C. McVeigh, G. E. M. Maguine, P. R. S. Maxwell and E. Q'Hanlon, Chem. Commun., 1996, 2191; A. P. De Silva, H. Q. N. Gunaratne, T. Gunnlaugsson, C. P. McCoy, P. R. S. Maxwell, J. T. Rademacher and T. E. Rice, Pure Appl. Chem., 1996, 68, 1443; A. P. De Silva, H. Q. N. Gunaratne, T. Gunnlaugsson, A. J. M. Huxley, C. P. McCoy, J. T. Rademacher and T. E. Rice, Chem. Rev., 1997, 97, 1515.
2. A. W. Czarnik, Acc. Chem. Res., 1994, 27, 302; A. W. Czarnik, Fluorescent Chemosensors for Ion and Molecular Recognition, ACS Books, Washington, DC, 1993.
3. T. D. James, K. R. A. S. Sandanayake and S. Shinkai, J. Chem. Soc., Chem. Commun., 1994, 477; T. D. James, K. R. A. S. Sandanayake and S. Shinkai, Angew. Chem., Int. Ed. Engl., 1994, 33, 2207; T. D. James, K. R. A. S. Sandanayake, R. Iguchi and S. Shinkai, J. Am. Chem. Soc., 1995, 117, 8982; T. D. James, P. Linnane and S. Shinkai, Chem. Commun., 1996, 281; T. D. James, H. Shinmori, M. Takeuchi and S. Shinkai, Chem. Commun., 1996, 705; T. D. James, H. Shinmori and S. Shinkai, Chem. Commun., 1997, 71.
4. For comprehensive reviews see: T. D. James, K. R. A. S. Sandanayake and S. Shinkai, Supramol. Chem., 1995, 6, 141; K. R. A. S. Sandanayake, T. D. James and S. Shinkai, Pure Appl. Chem., 1996, 68, 281; S. Shinkai and M. Takeuchi, Trends Anal. Chem., 1996, 15, 188; T. D. James, K. R. A. S. Sandanayake and S. Shinkai, Angew. Chem., Int. Ed. Engl., 1996, 35, 1910.
5. More recently, Cooper and James reported a PET chemosensor with an anthracene fluorophore appending an o-aminomethylphenyl boronic acid group and a crown ether group which selectively binds glucosamine: C. R. Cooper and T. D. James, Chem. Commun., 1997, 1419.
6. It is known that the amino group is capable of quenching the fluorescence of the (tetraphenylporphinato)tin(IV) moiety: R. Grigg and W. D. J. A. Norkert, J. Chem. Soc., Chem. Commun., 1992, 1298.
7. Computer simulations were performed using CDiscover as implemented by Insight II ver. 98.0 on a Silicon Graphics Octane workstation. Conformations were explored with molecular dynamics simulations using the ESFF forcefield at 500 K for 40 ps with subsequent minimisation of low energy conformations.
8. C. R. Cooper, N. Spencer and T. D. James, Chem. Commun., 1998, 1365.
9. An alternative mechanism was briefly considered after mass spectrometry consistently demonstrated the loss of one chloride ligand during measurements. Although this phenomenon could result simply from losing chloride to achieve a positive charge, we also considered the possibility of displacement of chloride by a boron-attached oxygen to yield a B–O–Sn self-complexed macrocycle. IR and NMR experiments produced no evidence for this interaction, however, and it was therefore discarded.