Page 101 - Catalysts for Fine Chemical Synthesis Vol 1 - Robert & Poignant

Catalysts for Fine Chemical Synthesis: Hydrolysis, Oxidation and Reduction. Volume 1
Edited by Stan M Roberts and Geraldine Poignant
Copyright  2002 John Wiley & Sons, Ltd.
ISBN: 0-471-98123-0

6 Epoxidation of Unfunctionalized
Alkenes and a, b-Unsaturated

Esters

CONTENTS
6.1 Asymmetric epoxidation of disubstituted Z-alkenes using a chiral
salen±manganese complex. . . . . . . . . . . . . . . . . 88
6.1.1 Epoxidation of (Z)-methyl styrene. . . . . . . . . . . . . . 89
6.1.2 Epoxidation of (Z)-ethyl cinnamate . . . . . . . . . . . . . 91
6.1.3 Conclusion . . . . . . . . . . . . . . . . . . . . . 93
6.2 Asymmetric epoxidation of disubstituted E-alkanes using a d-fructose
based catalyst . . . . . . . . . . . . . . . . . . . . 94
6.2.1 Epoxidation of (E)-stilbene . . . . . . . . . . . . . . . . 95
6.2.2 Conclusion . . . . . . . . . . . . . . . . . . . . . 97
6.3 Enantioselective epoxidation of (E)-b-methylstyrene by D 2 -symmetric
chiral trans-dioxoruthenium (VI) porphyrins
Rui Zhang, Wing-Yiu Yu and Chi-Ming Che . . . . . . . . . . . 98
6.3.1 Preparation of the trans-dioxoruthenium (VI) complexes
with D 2 -symmetric porphyrins (H 2 L 1±3 ) . . . . . . . . . . . . 98
6.3.2 Enantioselective epoxidation of (E)-b-methylstyrene . . . . . . . . 99
6.3.3 Conclusion . . . . . . . . . . . . . . . . . . . . . 100
References . . . . . . . . . . . . . . . . . . . . . . . 101

[1]
The methods developed by E. Jacobsen , using the salen ± manganese com-
[2]
plexes, and Y. Shi , using chiral ketones, permit the epoxidation of a large
range of disubstituted Z- or E-alkenes and trisubstituted alkenes. The method-
ology of Zhang, using porphyrins, is complementary.

Disubstituted Z-alkene Disubstituted E-alkene Trisubstituted alkene