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Beitrag zur asymmetrischen Synthese bicyclischer Verbindungen unter Katalyse mit optisch aktiven Aminosäuren. Synthese von (S)-2-Pyrrolidin-propionsäure und (R)-4-Amino-5-phenylvaleriansäure

✍ Scribed by Paul Buchschacher; Jean-Marie Cassal; Andor Fürst; Werner Meier


Publisher
John Wiley and Sons
Year
1977
Tongue
German
Weight
614 KB
Volume
60
Category
Article
ISSN
0018-019X

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✦ Synopsis


Contribution to the asymmetric synthesis of bicyclic compounds catalysed by optically active amino acids. Synthesis of (S)‐2‐pyrrolidinepropionic acid and (R)‐4‐amino‐5‐phenylvaleric acid

The evaluation of literature data concerning the asymmetric cyclization of the prochiral monocyclic triketones 1 to the enediones 3 shows that catalysis with optically active α‐amino acids of the (S)‐series leads to an excess of products having the same absolute configuration as natural steroids at C (13), while those of the (R)‐series favour the formation of the enantiomers (Scheme 1). With 1a as substrate an inverse asymmetric course was observed using the optically active β‐amino acids 5, 8 and 10 as catalysts (Table 1). Furthermore, the synthesis of the optically active γ‐amino acids 6 and 11 using the ArndtEistert process is described. The influence of these latter compounds on the asymmetric transformation of 1a into 3a has been investigated.