Enantiopure α-alkylidenelactones 7 were prepared by a Michael-like addition and ring-chain transformation affording optically active 4-(ω-hydroxyalkyl)pyrazolidin-3-Wittig reaction from α-bromolactones 4 and chiral aldehydes 6. Compounds 7 react with hydrazines 9 by stereoselective ones 11.
Synthesis of Chiral 4-(ω-Hydroxyalkyl)pyrazolidin-3-ones by Ring-Chain Transformation of α-Alkylidenelactones with Hydrazines
✍ Scribed by Andreas Otto; Burkhard Ziemer; Jürgen Liebscher
- Publisher
- John Wiley and Sons
- Year
- 1999
- Tongue
- English
- Weight
- 45 KB
- Volume
- 1999
- Category
- Article
- ISSN
- 1434-193X
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✦ Synopsis
The configuration and/or formulae of the following compounds need to be corrected. (1ЈR,E)-3-(2-Benzyloxy-3-hydroxypropylidene)dihydrofuran-2-one (7c): Correct formula: (4S,5R,4ЈS)-5-(2,2-Dimethyl[1,3]dioxolan-4-yl)-4-(2-hydroxyethyl)pyrazolidin-3-one (11a): Original formula correct (4R,5S,1ЈR)-5-(1-Benzyloxy-2-hydroxymethyl)-4-(2-hydroxyethyl)pyrazolidin-3-one (11g): Correct formula:
📜 SIMILAR VOLUMES
Synthesis of Chiral 4-(ω-Hydroxyalkyl)pyrazolidin-3-ones by Ring-Chain Transformation of α-Alkylidenelactones with Hydrazines. -This is the first access to optically active 4-(ω-hydroxyalkyl)pyrazolidin-3-ones. The lactone (IX), however, cannot be transformed into the corresponding pyrazolidinone.