## Abstract Basenkatalysierte Addition von Propiolsäure‐methylester an Oxazolin‐5‐one **1** ergibt Gemische der diastereomeren 3‐(5‐Oxo‐2‐phenyl‐2‐oxazolin‐4‐yl)acrylsäure‐methylester **2**, die nach hydrolytischer Ringöffnung zu **3** mit Bleitetraacetat die __(E)__‐3‐Acylacrylsäureester **5** lie
Synthese und Stereochemie von 4-Thiazolidinylphosphonsäureestern
✍ Scribed by Martens, Jürgen ;Kintscher, Jürgen ;Lindner, Karen ;Pohl, Siegfried ;Saak, Wolfgang ;Haase, Detlev
- Publisher
- John Wiley and Sons
- Year
- 1991
- Tongue
- English
- Weight
- 571 KB
- Volume
- 1991
- Category
- Article
- ISSN
- 0947-3440
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✦ Synopsis
Synthesis and Stereochemistry of Dimethyl 4‐Thiazolidinylphosphonates
Dimethyl phosphite adds to the azomethine bond of 2,5‐dihydrothiazoles 1 to produce dimethyl 4‐thiazolidinylphosphonates 2. Depending on the reaction conditions diastereomeric mixtures 2 are formed and explained by a two‐step mechanism. Assignment of configurations is proved by an X‐ray structure analysis of the thermodynamically more stable stereoisomer of 2c. N‐Acylated derivatives 5 could not be obtained by direct acylation of 2 but by a TiCl~4~‐catalyzed Michaelis‐Arbusov‐type reaction of trimethyl phosphite with N‐acyl‐4‐methoxythiazolidines 3. Phosphonates 5 are formed with high diastereoselectivity.
📜 SIMILAR VOLUMES
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The structure of the antibiotic verrucarin E (C,H,O,N) is shown to be that of 2-hydroxymeth yl-4-acetyl-pyrrole (1). ## Institut fur Organische Chemie der Universitgt Basel LITEKATL'R~EHZElCH?r'lS [I] 9. JMitteilung: E. F m z , B. BOHNER & CH. TAMM, Helv. 48, 1669 (1965).
Die gefundenen Werte fur C, H und N stimmen mit den berechneten uberein. ") Umkristallisation aus CH,OH; b, I, 11,111 in Dioxan; ") IV in CH,OH; d, in Nujol Tabelle 2 Ver-'H-NMR (HMDS) bin--CH,im -CH,Xa) CH,Odung Cykloalkanring CH3-Ph