✦ LIBER ✦
Asymmetric halogenation of camphor-10-sulfonic acid derived esters: an efficient new route to enantiomerically pure halohydrins and epoxides.
✍ Scribed by Wolfgang Oppolzer; Philip Dudfield
- Book ID
- 104233289
- Publisher
- Elsevier Science
- Year
- 1985
- Tongue
- French
- Weight
- 245 KB
- Volume
- 26
- Category
- Article
- ISSN
- 0040-4039
No coin nor oath required. For personal study only.
✦ Synopsis
Successive treatment of chiral esters J_ with LDA/Me3SiCl and NBS or NCS gave crystalline a-haloesters 2 which furnished halohydrins 4 and terminal epoxides 2 in high e.e.. The practical, chiral auxiliaries Xa and Xb (Scheme 1) confer high II-face differentiation to Diels-Alder-l and organocopper additions of conjugated enoates' as well as a-alkylations3 and -acetoxylations3 of enolates.