Polyamino acid-catalysed asymmetric epoxidation: Sodium percarbonate as a source of base and oxidant

Tetrahedron Letters

Volumn 40, Issue 29, 1999, Pages 5417-5420

  Allen, Joanne V ^a   Drauz, Karl Heinz ^b   Flood, Robert W ^a   Roberts, Stanley M ^a   Skidmore, John ^a  

^a UNIVERSITY OF LIVERPOOL   (United Kingdom)

^b EVONIK INDUSTRIES AG   (Germany)

Author keywords

Asymmetric reactions; Enones; Epoxidation; Peptides and polypeptides

Indexed keywords

BASE; CARBONIC ACID DERIVATIVE; OXIDIZING AGENT; PERCARBONATE SODIUM; POLYAMINOACID; UNCLASSIFIED DRUG;

ARTICLE; CATALYSIS; CHEMICAL REACTION; CHEMICAL REACTION KINETICS; CHEMICAL STRUCTURE; EPOXIDATION;

EID: 0033575469     PISSN: 00404039     EISSN: None     Source Type: Journal    
DOI: 10.1016/S0040-4039(99)01021-7     Document Type: Article

References (15)

1. Juliá, S.; Masana, J.; Vega, J. C. Angew. Chem. Int. Ed. Engl., 1980, 19, 929.
2. Cooper, M. S.; Heaney, H.; Newbold, A. J.; Sanderson, W. R. Synlett, 1990, 533.
3. Adger, B. M.; Barkley, J. V.; Bergeron, S.; Cappi, M. W.; Flowerdew, B. E.; Jackson, M. P.; McCague, R.; Nugent, T. C.; Roberts, S. M. J. Chem. Soc., Perkin Trans. 1, 1997, 3501.
4. A number of recent reviews have been published, see for example Ebrahim, S.; Wills, M. Tetrahedron: Asymmetry, 1997, 8, 3163; Pu, L. Tetrahedron: Asymmetry, 1998, 9, 1457.
5. A number of recent reviews have been published, see for example Ebrahim, S.; Wills, M. Tetrahedron: Asymmetry, 1997, 8, 3163; Pu, L. Tetrahedron: Asymmetry, 1998, 9, 1457.
6. Cappi, M. W.; Chen, W.-P.; Flood, R. W.; Liao, Y.-W.; Roberts, S. M.; Skidmore, J.; Smith, J. A.; Williamson, N. M. Chem. Commun., 1998, 1159.
7. Bentley, P. A.; Cappi, M. W.; Flood, R. W.; Roberts, S. M.; Smith, J. A. Tetrahedron Lett., 1998, 39, 9297.
8. The preparative scale catalysts are synthesised by polymerisation of the amino acid N-carboxyanhydride. The diminished activity shown by the defined length peptides reflects lower loading of the peptide on the support and in some cases, changes made to the peptide structure.
9. McKillop, A.; Sanderson, W. R. Tetrahedron, 1995, 51, 6145.
10. Muzart, J. Synthesis, 1995, 1325.
11. Ando, T.; Cork, D. G.; Kimura, T. Chem. Lett., 1986, 665.
12. Lasterra-Sánchez, M. E.; Felfer, U.; Mayon, P.; Roberts, S. M.; Thornton, S. R.; Todd, C. J. J. Chem. Soc., Perkin Trans. 1, 1996, 343.
13. We typically use poly-L-leucine immobilised on a polystyrene support (i-PLL) see Itsuno, S.; Sakakura, M.; Ito, K. J. Org. Chem., 1990, 55, 6047.
14. We have found that the catalytic activity of polyamino acid catalysts can be improved by an activation procedure. This involves stirring the catalyst in a mixture of toluene (10 cm3/g) and 4M sodium hydroxide (4 cm3/g) for between 1 and 5 days. The catalyst is separated by filtration, washed with water, 1:1 water:acetone and acetone and dried before use. The mechanism of this activation procedure is currently not clear.
15. Bentley, P. A.; Roberts, S. M. unpublished results.