Sharpless epoxidation

The Sharpless epoxidation reaction is an enantioselective chemical reaction to prepare 2,3-epoxyalcohols from primary and secondary allylic alcohols.^[1][2] This reaction gives good yields and enantioselectivities over a broad range of substrates.

Additional recommended knowledge

Recognize and detect the effects of electrostatic charges on your balance

Essential Laboratory Skills Guide

What is the Sensitivity of my Balance?

The oxidizing agent is t-butylperoxide. Enantioselectivity is achieved by a catalyst formed from titanium tetra(isopropoxide) and diethyl tartrate. Only 5-10 mol% of the catalyst in the presence of 3Å molecular sieves (3Å MS) is necessary.^[3]

Several reviews have been published.^[4][5][6][7]

Epoxides can be easily converted into dialcohols, aminoalcohols or ethers, so formation of chiral epoxides is a very important step in the synthesis of natural products. K. Barry Sharpless shared the Nobel prize in 2001 for his work on asymmetric oxidations. The prize was shared with William S. Knowles and Ryoji Noyori.

Reaction mechanism

The Sharpless group has investigated both the reaction kinetics^[8] and the structure of the catalyst^[9].

See also

• Asymmetric catalytic oxidation

References

1. ^ Katsuki, T.; Sharpless, K. B. J. Am. Chem. Soc. 1980, 102, 5974. (doi:10.1021/ja00538a077)
2. ^ Hill, J. G.; Sharpless, K. B.; Exon, C. M.; Regenye, R. Org. Syn., Coll. Vol. 7, p.461 (1990); Vol. 63, p.66 (1985). (Article)
3. ^ Gao, Y.; Hanson, R. M.; Klunder, J. M.; Ko, S. Y.; Masamune, H.; Sharpless, K. B. J. Am. Chem. Soc. 1987, 109, 5765-5780. (doi:10.1021/ja00253a032)
4. ^ Johnson, R. A.; Sharpless, K. B. Comp. Org. Syn. 1991, 7, 389-436. (Review)
5. ^ Hüft, E. Top. Curr. Chem. 1993, 164, 63-77. (Review)
6. ^ Katsuki, T.; Martin, V. S. Org. React. 1996, 48, 1-300. (Review)
7. ^ Pfenninger, A. Synthesis 1986, 89-116. (Review)
8. ^ Woodard, S. S.; Finn, M. G.; Sharpless, K. B. J. Am. Chem. Soc. 1991, 113, 106-113. (doi:10.1021/ja00001a018)
9. ^ Finn, M. G.; Sharpless, K. B. J. Am. Chem. Soc. 1991, 113, 113-126. (doi:10.1021/ja00001a019)