The order of lithium ion affinities for the 20 common α-amino acids. Calculation of energy-well depth of ion-bound dimers

Abstract

In an earlier publication it was shown that the kinetic method for determination of proton affinities can be satisfactorily explained when the critical energies for decomposition of the proton-bound dimers are calculated from the Marcus equation. In this work it is shown that the critical energies for decomposition of alkali metal ion-bound dimers also seem to follow the Marcus equation. This supports the application of the kinetic method for measurements of alkali metal-ion affinities of organic molecules. Based on unimolecular decompositions of Li⁺-bound dimers, the order of lithium ion affinity of the common α-amino acids has been established as: Arg > His > Gln > As n > Lys > Trp > Glu > Asp > Tyr > Met > Phe > Thr > Pro > Ser > Ile > Leu > Val > Cys > Ala > Gly.

References

1. (a) G. Bojesen, J. Chem. Soc., Chem. Commun., 1986, 244; (b) G. Bojesen, J. Am. Chem. Soc., 1990, 112, 5095; (c) G. Bojesen, T. Breindahl and U. N. Andersen, Org. Mass Spectrom., 1993, 28, 1448; (d) G. Bojesen and T. Breindahl, J. Chem. Soc., Perkin Trans. 2, 1994, 1029; (e) S. B. Nielsen and G. Bojesen, Eur. Mass Spectrom., 1995, 1, 423.
2. (a) R. G. Cooks and T. L. Kruger, J. Am. Chem. Soc., 1977, 99, 1279; (b) S. A. McLuckey, D. Cameron and R. G. Cooks, J. Am. Chem. Soc., 1981, 103, 1313; (c) R. G. Cooks, J. S. Patrick, T. Kotiaho and S. A. McLuckey, Mass Spectrom. Rev., 1994, 13, 287.
3. R. A. Marcus, J. Chem. Phys., 1968, 72, 891.
4. (a) M. J. Pellerite and J. I. Brauman, J. Am. Chem. Soc., 1983, 105, 2672; (b) J. A. Dodd and J. I. Brauman, J. Am. Chem. Soc., 1984, 106, 5356; (c) J. A. Dodd and J. I. Brauman, J. Phys. Chem., 1986, 90, 3559; (d) J. A. Dodd, S. Baer, C. R. Moylan and J. I. Brauman, J. Am. Chem. Soc., 1991, 113, 5942; (e) B. D. Wladkowski and J. I. Brauman, J. Phys. Chem., 1993, 97, 13 158.
5. (a) S. W. Benson and J. H. Buss, J. Chem. Phys., 1958, 29, 546; (b) N. Cohen and S. W. Benson, Chem. Rev., 1993, 93, 2419.
6. J. R. Murdoch, J. Am. Chem. Soc., 1983, 105, 2159.
7. D. E. Magnoli and J. R. Murdoch, J. Am. Chem. Soc., 1981, 103, 7465.
8. (a) J. Summer, K. Nishizawa and P. Kebarle, J. Phys. Chem., 1981, 85, 1814; (b) B. L. Upshulte, F. J. Schelling, R. G. Keesee and A. W. Castleman, Chem. Phys. Lett., 1984, 111, 389; (c) K. I. Peterson, T. D. Märk, R. G. Keesee and A. W. Castleman, J. Phys. Chem., 1984, 88, 2880.
9. M. J. Lacey and C. G. Macdonald, Org. Mass Spectrom., 1977, 12, 587.
10. (a) G. Puzo, J. C. Promé and J.-J. Fournié, Anal. Chem., 1985, 57, 892; (b) J. J. Fournié and G. Puzo, Anal. Chem., 1985, 57, 2287; (c) G. Puzo, J. C. Promé and J.-J. Fournié, Carbohydrate Res., 1985, 140, 131; (d) M. Sawada, L. Ouyang, Y. Takai, H. Yamada, T. Hanafusa, T. Kinoshita and T. Mochizuki, Chem. Lett., 1990, 1361; (e) S. Maleknia and J. Brodbelt, J. Am. Chem. Soc., 1992, 114, 4295; (f) O. Burlet and S. J. Gaskell, J. Am. Soc. Mass Spectrom., 1993, 4, 461; (g) I. H. Chu, H. Zhang and D. V. Dearden, J. Am. Chem. Soc., 1993, 115, 5736.
11. (a) S. A. McLuckey, A. E. Schoen and R. G. Cooks, J. Am. Chem. Soc., 1982, 104, 848; (b) F. Strobel and D. P. Ridge, Inorg. Chem., 1988, 27, 891; (c) K. Eller and H. Schwarz, Organometallics, 1989, 8, 1820; (d) L.-Z. Chen and J. M. Miller, Org. Mass Spectrom., 1992, 27, 883; (e) H. Becker, D. Schröder, W. Zummack and H. Schwarz, J. Am. Chem. Soc., 1994, 116, 1096.
12. H.-F. Grützmacher and A. Caltapanides, J. Am. Soc. Mass Spectrom., 1984, 5, 826.
13. B. A. Cerda and C. Wesdemiotis, J. Am. Chem. Soc., 1995, 117, 9734.
14. (a) K. Isa, T. Omote and M. Amayas, Org. Mass Spectrom., 1990, 25, 620; (b) Z. Wu and C. Fenselau, Rapid Commun. Mass Spectrom., 1992, 6, 403; (c) X. Li and A. G. Harrison, Org. Mass Spectrom., 1993, 28, 366.
15. G. S. Gorman, J. P. Speir, C. A. Turner and I. J. Amster, J. Am. Chem. Soc., 1992, 114, 3986.
16. B. Shushan and R. K. Boyd, Int. J. Mass Spectrom. Ion Phys., 1980, 34, 37.
17. (a) F. Jensen, J. Am. Chem. Soc., 1992, 114, 9533; (b) S. Bouchonnet and Y. Hoppilliard, Org. Mass Spectrom., 1992, 27, 71.
18. (a) R. H. Staley and J. L. Beauchamp, J. Am. Chem. Soc., 1975, 97, 5920; (b) R. L. Woodin and J. L. Beauchamp, J. Am. Chem. Soc., 1978, 100, 501.
19. (a) R. W. Taft, F. Anvia, J.-F. Gal, S. Walsh, M. Capon, M. C. Holmes, K. Hosn, G. Oloumi, R. Vasanwala and S. Yazdani, Pure Appl. Chem., 1990, 62, 17; (b) F. Anvia, S. Walsh, M. Capon, I. A. Koppel, R. W. Taft, J. L. G. dePass and J. Catalan, J. Am. Chem. Soc., 1990, 112, 5095.