Preparation of enantiomerically pure pyrazolines by an enantioconvergent process
β Scribed by Bosum-Dybus, Annegrit ;Neh, Harribert
- Publisher
- John Wiley and Sons
- Year
- 1991
- Tongue
- English
- Weight
- 289 KB
- Volume
- 1991
- Category
- Article
- ISSN
- 0947-3440
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β¦ Synopsis
Abstract
Derivatization of insecticidally active racβpyrazoline 2 with (1__S__)β(β)βcamphanic acid chloride led to the separable diastereomers 3a and 3b. Regioselective cleavage to the enantiomerically pure pyrazolines 2a and 2b was achieved under mild conditions. Diastereomer 3b was transformed into diastereomer 3a by crystallization under equilibrating conditions making the overall process enantioconvergent.
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