Enhancement of the enantioselectivity in the epoxidation of sterically hindered substrates by decreasing the contribution of the blank reaction

Tetrahedron Asymmetry

Volumn 8, Issue 18, 1997, Pages 3039-3042

  Janssen, Kristien B M ^a   Parton, Rudy F ^a   Jacobs, Pierre A ^a  

^a UNIVERSITY OF LEUVEN   (Belgium)

Author keywords

[No Author keywords available]

Indexed keywords

EPOXIDE;

ARTICLE; CATALYSIS; CHIRALITY; DRUG SYNTHESIS; ENANTIOMER; EPOXIDATION; IN VITRO STUDY; METHODOLOGY; PRIORITY JOURNAL; REACTION ANALYSIS; STEREOCHEMISTRY;

EID: 0030921894     PISSN: 09574166     EISSN: None     Source Type: Journal    
DOI: 10.1016/S0957-4166(97)00367-4     Document Type: Article

References (15)

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2. (b) N.H. Lee, A.R. Muci, E.N. Jacobsen, Tetrahedron Lett., 32, 1991, 5055;
3. (c) N.H. Lee, E.N. Jacobsen, Tetrahedron Lett., 32, 1991, 6533;
4. (d) M. Palucki, P. Hanson, E.N. Jacobsen, Tetrahedron Lett., 33, 1992, 7111.
5. B.D. Brandes, E.N. Jacobsen, J. Org. Chem., 59, 1994, 4378.
6. D. Bell, M.R. Davies, F.J.L. Finney, G.R. Geen, P.M. Kincey, I.S. Mann, Tetrahedron Lett., 37, 1996, 3895.
7. (a) L. Deng, E.N. Jacobsen, J. Org. Chem., 57, 1992, 4320;
8. (b) R. Irie, Y. Ito, T. Katsuki, Synlett, 1991, 265.
9. E.N. Jacobsen, L. Deng, Y. Furukawa, L.E. Martínez, Tetrahedron, 50, 1994, 4323.
10. (a) T. Katsuki, Coord. Chem. Rev., 140, 1995, 189;
11. (b) T. Katsuki, J. Mol. Cat. A: Chemical, 113, 1996, 87.
12. 2 were carried out at 4°C in 22.5 ml solvent, with 2.235 mmol substrate and 3.351 mmol NaOCl (13% solution in water). The reactions in ether were carried out in 7.5 ml solvent with 0.745 mmol substrate and 1.117 mmol NaOCL. S/C is varied by changing the amount of catalyst at a constant quantity of 1-phenyl-1-cyclohexene. The results are obtained after 4 hours of reaction.
13. [NaOCl] solved in the organic phase can be held constant, because it is used in excess, and is combined in the rate constant.
14. kcatal.+kblank with 92 the highest ee obtained (S/C=15).
15. I.F.J. Vankelecom, D. Tas, R.F. Parton, V. Van de Vyver, P.A. Jacobs, Angew. Chem. Int. Ed. Engl., 35, 1996, 1346.