Hammett analysis of a family of carbene-carbene complex equilibria

Organic Letters

Volumn 13, Issue 5, 2011, Pages 1198-1201

  Wang, Lei ^a   Moss, Robert A ^a   Thompson, Jack ^a   Krogh Jespersen, Karsten ^a  

^a RUTGERS UNIVERSITY   (United States)

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Indexed keywords

EID: 79952164199     PISSN: 15237060     EISSN: 15237052     Source Type: Journal    
DOI: 10.1021/ol200083a     Document Type: Article

References (19)

1. Moss, R. A.; Wang, L.; Odorisio, C. M.; Krogh-Jespersen, K. J. Am. Chem. Soc. 2010, 132, 10677
2. For other examples of carbene complexes, see: Tippmann, E. M.; Platz, M. S.; Svir, I. B.; Klymenko, O. V. J. Am. Chem. Soc. 2004, 126, 5750
3. Wang, J.; Kubicki, J.; Peng, H.; Platz, M. S. J. Am. Chem. Soc. 2008, 130, 6604
4. Graham, W. H. J. Am. Chem. Soc. 1965, 87, 4396
5. Moss, R. A.; Terpinski, J.; Cox, D. P.; Denney, D. Z.; Krogh-Jespersen, K. J. Am. Chem. Soc. 1985, 107, 2743. Full experimental details for the benzamidine preparations appear in this publication
6. Moss, R. A.; Wang, L.; Weintraub, E.; Krogh-Jespersen, K. J. Phys. Chem. A 2008, 112, 4651
7. 2 excimer laser emitting 14 ns light pulses at 351 nm with 55-65 mJ power. For more details, see: Moss, R. A.; Tian, J.; Sauers, R. R.; Ess, D. H.; Houk, K. N.; Krogh-Jespersen, K. J. Am. Chem. Soc. 2007, 129, 5167
8. The σ → p absorption of 1d appears at 588 nm. (1, 8)
9. Pliego, J. R., Jr.; De Almeida, W. B.; Celebi, S.; Zhu, Z.; Platz, M. S. J. Phys. Chem. A 1999, 103, 7481
10. Calibration corrects the raw UV-vis absorptions for wavelength-dependent variations in sample absorptivity, xenon monitoring lamp emission, and detector sensitivity. (1) Calibration spectra are collected in the Supporting Information.
11. The spectra for carbene 1d (X = H) and its TMB complexes appear in ref 1 and its Supporting Information.
12. 1 (0.105) is the computed oscillator strength for complex 2c at 483 nm (assigned to the observed absorption at 500 nm). See the Supporting Information for details.
13. Smith, M. B.; March, J. March's Advanced Organic Chemistry, 6 th ed.; Wiley Interscience: Hoboken, NJ, 2007; p 404.
14. The absorptions used to calculate K are those corresponding to the computed absorptions for the B -type complexes of Figure 2. The observed absorptions assigned to the A -type complexes overlap significantly with the " B " absorptions and cannot be separately evaluated; cf. the absorption spectra in the Supporting Information.
15. Jaffe, H. H. Chem. Rev. 1953, 53, 191
16. Wells, P. R. Chem. Rev. 1963, 63, 171
17. Rondan, N. G.; Houk, K. N.; Moss, R. A. J. Am. Chem. Soc. 1980, 102, 1770
18. All calculations made use of the Gaussian 09, Revision A02 program package: Frisch, M. J.. Gaussian, Inc.: Wallingford, CT, 2009; see Supporting Information for additional computational details and the complete reference for Gaussian 09.
19. It was necessary to tighten the geometry optimization criteria and to increase the size of the integration grid relative to their default values to reach even this level of agreement and consistency. Test calculations with larger basis sets and/or different dispersion-corrected functionals did not show any improvement for X = MeO.