The use of ionic chiral sensitizers in the crystalline state: Application to the di-π-methane photorearrangement of a benzonorbornadiene derivative

Tetrahedron Letters

Volumn 40, Issue 50, 1999, Pages 8725-8728

  Janz, Kristin M ^a   Scheffer, John R ^a  

^a UNIVERSITY OF BRITISH COLUMBIA   (Canada)

Author keywords

Ammonium salts; Asymmetric induction; di methane rearrangement; Photochemistry

Indexed keywords

AMINE; BENZONORBORNADIENE DERIVATIVE; CARBOXYLIC ACID; INORGANIC SALT; NORBORNADIENE DERIVATIVE; UNCLASSIFIED DRUG;

ARTICLE; ENANTIOMER; ENERGY TRANSFER; IRRADIATION; OPTICAL ROTATION; PHOTOCHEMISTRY; PHOTOLYSIS; RACEMIC MIXTURE; REACTION ANALYSIS;

EID: 0033544758     PISSN: 00404039     EISSN: None     Source Type: Journal    
DOI: 10.1016/S0040-4039(99)01865-1     Document Type: Article

References (21)

1. The sign of rotation given for compounds 2 and 3 is arbitrary and used for illustrative purposes only.
2. Pasteur, L. C. R. Acad. Sci. 1853, 37, 162.
3. (a) Jacques, J.; Collet, A.; Wilen, S. H. Enantiomers, Racemates and Resolutions; Wiley: New York, 1981;
4. (b) Eliel, E. L.; Wilen, S. H. Stereochemistry of Organic Compounds; Wiley: New York, 1994; Chapter 7;
5. (c) Collet, A. Angew. Chem., Int. Ed. Engl. 1999, 37, 3239.
6. (a) Cheung, E.; Netherton, M. R.; Scheffer, J. R.; Trotter, J. J. Am. Chem. Soc. 1999, 121, 2919;
7. (b) Leibovitch, M.; Olovsson, G.; Scheffer, J. R.; Trotter, J. J. Am. Chem. Soc. 1998, 120, 12755;
8. (c) Gamlin, J. N.; Jones, R.; Leibovitch, M.; Patrick, B.; Scheffer, J. R.; Trotter, J. Acc. Chem. Res. 1996, 29, 203.
9. Edman, J. R. J. Am. Chem. Soc. 1966, 88, 3454; ibid, 1969, 91, 7103.
10. Edman, J. R. J. Am. Chem. Soc. 1966, 88, 3454; ibid, 1969, 91, 7103.
11. Tufariello, J. J.; Rowe, D. W. J. Org. Chem. 1971, 36, 2057.
12. Paquette and co-workers have studied the solution phase photochemistry of a variety of aryl, bridgehead and vinyl-substituted benzonorbornadiene derivatives: Paquette, L. A.; Burke, L. D. J. Org. Chem. 1987, 52, 2674 and references cited therein.
13. (a) Hammond, G. S.; Cole, R. S. J. Am. Chem. Soc. 1965, 87, 3256;
14. (b); Inoue, Y.; Matsushima, E.; Wada, T. J. Am. Chem. Soc. 1998, 120, 10687.
15. For an example of the use of an achiral ionic triplet energy sensitizer in the crystalline state, see: Gamlin, J. N.; Olovsson, G.; Pitchumani, K.; Ramamurthy, V.; Scheffer, J. R.; Trotter, J. Tetrahedron Lett. 1996, 37, 6037. Recently, Ramamurthy et al. have shown that modest (ca. 15% ee) levels of asymmetric induction can be generated in photoproduct 5a by irradiation of benzonorbornadiene in the zeolite TIY containing ephedrine hydrochloride. See: Joy, A.; Robbins, R. J.; Pitchumani, K.; Ramamurthy, V. Tetrahedron Lett. 1997, 38, 8825.
16. For an example of the use of an achiral ionic triplet energy sensitizer in the crystalline state, see: Gamlin, J. N.; Olovsson, G.; Pitchumani, K.; Ramamurthy, V.; Scheffer, J. R.; Trotter, J. Tetrahedron Lett. 1996, 37, 6037. Recently, Ramamurthy et al. have shown that modest (ca. 15% ee) levels of asymmetric induction can be generated in photoproduct 5a by irradiation of benzonorbornadiene in the zeolite TIY containing ephedrine hydrochloride. See: Joy, A.; Robbins, R. J.; Pitchumani, K.; Ramamurthy, V. Tetrahedron Lett. 1997, 38, 8825.
17. Buske, G. R.; Ford, W. T. J. Org. Chem. 1976, 41, 1998.
18. Cheung, E.; Trotter, J. Unpublished results.
19. All new compounds described in the present paper gave spectroscopic data and elemental analyses completely in accord with their assigned structures. Details will be provided in a subsequent full paper.
20. It is likely that this material is a hydrogen bonded complex, since p-acetylpyridine is not sufficiently basic to remove a proton from carboxylic acid 4c.
21. The chiral sensitizers 7 and 8 were synthesized by DCC coupling of the appropriate N-carbobenzyloxy-protected amino acid to p-acetylbenzyl alcohol or p-hydroxybenzophenone, followed by deprotection with HBr in acetic acid.