There have been developed several kinds of asymmetric syntheses for preparing optically active a-hydroxy acids, ') and high optical induction(>80% e.e.) can be successfully achieved by selecting chiral sources lb) or by
Asymmetric bromolactonization reaction: Synthesis of optically active 2-hydroxy-2-methylalkanoic acids from 2-methylenealkanoic acids
โ Scribed by Paul F Corey
- Publisher
- Elsevier Science
- Year
- 1987
- Tongue
- French
- Weight
- 207 KB
- Volume
- 28
- Category
- Article
- ISSN
- 0040-4039
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โฆ Synopsis
Optically pure 2-hydroxy-2-methylalkanoic acids of either configuration may be obtained via an asymmetric bromolactonization reaction using &-proline as a chiral auxilliary.
๐ SIMILAR VOLUMES
## Abstract The reaction of (+)โcarโ2โene (**4**) with chlorosulfonyl isocyanate (=sulfuryl chloride isocyanate; ClSO~2~NCO) led to the tricyclic lactams **6** and **8** corresponding to the initial formation both of the tertiary carbenium and __ฮฑ__โcyclopropylcarbenium ions (__Schemeโ 2__). A numbe
The sequential Michael reaction of (S)-4,5-di-O-isopropylidenepent-2enoate la and lb with lithium enolate 2 afforded diastereo-and enantioselec--tively bicyclo[2.2.2]octane 2 and 6 (or 51, respectively. The adducts were efficiently converted into both enantiomeric keto aldehydes c-j-7 and (+)-I. Bic