Asymmetric benzylic oxidation using a Mn-salen complex as catalyst

Tetrahedron Letters

Volumn 37, Issue 28, 1996, Pages 4979-4982

  Hamachi, Kiyoe ^a   Irie, Ryo ^a   Katsuki, Tsutomu ^a  

^a KYUSHU UNIVERSITY   (Japan)

Author keywords

[No Author keywords available]

Indexed keywords

BENZENE DERIVATIVE; BENZYL ALCOHOL; CHLOROBENZENE; FLUOROBENZENE; INDAN DERIVATIVE; SOLVENT;

ARTICLE; CATALYST; OXIDATION; STEREOCHEMISTRY;

EID: 0030575425     PISSN: 00404039     EISSN: None     Source Type: Journal    
DOI: 10.1016/0040-4039(96)00984-7     Document Type: Article

References (13)

1. 1. For a review, see: Collmann, J. P.; Zhang, X.; Lee, V. J.; Uffelman, E. S.; Brauman, J. I. Science 1993, 267, 1404-1411.
2. 2. Recently highly enantioselective allylic oxidation using bis(oxazolines)-Cu or tris(oxazolines)-Cu complex as a catalyst has been reported, a) Gokhale, A. S.; Minidis, A. B. E.; Pfaltz, A. Tetrahedron Lett. 1995, 36, 1831-1834.
3. b) Andrus, M. B.; Argade, A. B.; Chen, X.; Pamment, M. G. Tetrahedron Lett. 1995, 36, 2945-2948.
4. c) Kawasaki, K.; Tsumura, S.; Katsuki, T. Synlett 1995, 1245-1246.
5. 3. Groves, J. T.; Viski, T. J. Org Chem. 1990, 55, 3628-3634.
6. 4. a) Katsuki, T. Coord. Chem. Rev. 1995, 140, 189-214.
7. b) Katsuki, T. J. Synth. Org. Chem. Jpn 1995, 53, 940-951.
8. c) Jacobsen, E. N. In "Catalytic Asymmetric Synthesis" ed by I. Ojima, VCH publishers, Inc., New York, (1993), pp 159-202.
9. 5. Kaufman, M. D.; Grieco, P. A.; Bougie, D. W. J. Am. Chem. Soc. 1993, 115, 11648-11649.
10. 6. Larrow, J. F.; Jacobsen, E. N. J. Am. Chem. Soc. 1994, 116, 12129-12130.
11. 7. Racemic 6 was synthesized according to the reported procedure: Newman, M. S.; Dali, H. M.; Hung, W. M. J. Org. Chem. 1975, 40, 262-265. Absolute configurations of 5 and 6 are unknown. Enantiomeric excesses of 5 and 6 were determined by capillary GLC using optically active column (β-DEX™ 120).
12. 8. Since epoxidation of simple olefins and oxidation of sulfides with Mn-salen complexes proceed with high enantioselectivity (reference 4a), high enantioselectivity in the hydrogen abstraction step can very reasonably be expected.
13. 9. Although the yield of the desired product was not very high under the present reaction conditions, prolongation of the reaction time did not improve the yield. This may suggest the decay of the catalyst during the reaction, but the enantioselectivity of the product did not change in the observed reaction time. The reaction with pentafluoroiodosylbenzene as oxidant also showed the same enantioselectivity.