Chlorofluorocarbene: First UV observation of a dihalocarbene in solution

Organic Letters

Volumn 9, Issue 20, 2007, Pages 4053-4056

  Moss, Robert A ^a   Tian, Jingzhi ^a   Sauers, Ronald R ^a   Skalit, Christopher ^a   Krogh Jespersen, Karsten ^a  

^a RUTGERS UNIVERSITY   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 35048874129     PISSN: 15237060     EISSN: None     Source Type: Journal    
DOI: 10.1021/ol701804m     Document Type: Article

References (26)

1. Moss, R. A. Acc. Chem. Res. 2006, 39, 267.
2. Graham, W. H. J. Am. Chem. Soc. 1965, 87, 4396.
3. Moss, R. A. In Chemistry of Diazirines; Liu, M.T.H., Ed.; CRC Press: Boca Raton, FL, 1987; Vol. 1, p 99f.
4. Moss, R. A.; Chu, G.; Sauers, R. R. J. Am. Chem. Soc. 2005, 127, 2408.
5. Chu, G.; Moss, R. A.; Sauers, R. R. J. Am. Chem. Soc. 2005, 127, 14206.
6. Moss, R. A.; Tian, J.; Sauers, R. R.; Ess, D. H.; Houk, K. N.; KroghJespersen, K. J. Am. Chem. Soc. 2007, 129, 5167.
7. Chateauneuf, J. E.; Johnson, R. P.; Kirchoff, M. M. J. Am. Chem. Soc. 1990, 112, 3217.
8. Tippmann, E. M.; Platz, M. S. J. Phys. Chem. A 2003, 107, 8547.
9. Mitsch, R. A.; Neuvar, E. W.; Koshar, R. J.; Dybvig, D. H. J. Heterocycl. Chem. 1965, 2, 371.
10. Mitsch, R. A. J. Org. Chem. 1968, 33, 1847.
11. Fedé, J.-M.; Jockusch, S.; Lin, N.; Moss, R. A.; Turro, N. J. Org. Lett. 2003, 5, 5027.
12. Moss, R. A.; Perez, L. A.; Wlostowska, J.; Guo, W.; KroghJespersen, K. J. Org. Chem. 1982, 47, 4177.
13. See the Supporting Information for experimental details.
14. (a) Cox, D. P.; Moss, R. A.; Terpinski, J. J. Am. Chem. Soc. 1983, 105, 6513.
15. (b) Moss, R. A.; Terpinski, J.; Cox, D. P.; Denney, D. Z.; KroghJespersen, K. J. Am. Chem. Soc. 1985, 107, 2743.
16. Smith, C. E.; Milligan, D. E.; Jacox, M. E. J. Chem. Phys. 1971, 54, 2780.
17. A reviewer has noted that the ClCF absorption is surprisingly narrow for a HOMO to LUMO carbene band. At its base, it spans ∼100 nm. In comparison, the HOMO to LUMO absorption of MeCCl in pentane solution spans ∼200 nm (Moss, R. A.; Tian, J.; Sauers, R. R.; Krogh-Jespersen, K. J. Am. Chem. Soc. 2007, 129, 10019). There are very few HOMO-LUMO bands of carbenes in solution to afford further comparisons. Note that we do not observe diazirine bleaching in Figure 1 ; only about 0.1% of the diazirine is destroyed per laser pulse.
18. From the Y-intercept of this correlation, we derive a lifetime of ∼0.2 μs for ClCF in pentane under our reaction conditions.
19. Jackson, J. E.; Soundararajan, N.; Platz, M. S.; Liu, M. T. H. J. Am. Chem. Soc. 1988, 110, 5595.
20. 20 showed that the appropriate cyclopropane was produced when diazirine 1 was photolyzed in tetramethylethylene.
21. Dolbier, W. R., Jr.; Burkholder, C. R. J. Org. Chem. 1990, 55, 589.
22. We estimate the errors in the rate constants at 10-15%. All of the correlation constants (r), from which the rate constants derive, are >0.99.
23. (a) Moss, R. A. In Carbene Chemistry From Fleeting Intermediates to Powerful Reagents; Bertrand, G., Ed.; Dekker-Fontis: New York, 2002; pp 57f.
24. (b) Moss, R. A. Acc. Chem. Res. 1989, 22 15.
25. (c) Moss, R. A. Acc. Chem. Res. 1980, 13, 58.
26. 2 complexes are ΔG‡ = 15.8 and 11.7 kcal/ mol, respectively, whereas the respective free energies of reaction are ΔG = 4.2 and -3.8 kcal/mol.