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Optical Resolution of 5‐Oxo‐1‐Phenyl‐Pyrazolidine‐3‐Carboxylic Acid as a New Organocatalyst for Organic Reactions
Author(s) -
Tzeng ZhengHao,
Yang ShuenWen,
Liu PangMin,
Chen KwunMin
Publication year - 2008
Publication title -
journal of the chinese chemical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.329
H-Index - 45
eISSN - 2192-6549
pISSN - 0009-4536
DOI - 10.1002/jccs.200800091
Subject(s) - diastereomer , chemistry , carboxylic acid , yield (engineering) , column chromatography , resolution (logic) , cleavage (geology) , organic chemistry , medicinal chemistry , stereochemistry , materials science , geotechnical engineering , fracture (geology) , engineering , metallurgy , artificial intelligence , computer science
Abstract Optical resolution of racemic 5‐oxo‐1‐phenyl‐pyrazolidine‐3‐carboxylic acid 2 with L‐amino acid methyl ester via the diastereomers formation was investigated. Treatment of racemic 5‐oxo‐1‐phenyl‐pyrazolidine‐3‐carboxylic acid 2 with L‐valine methyl ester gave diastereomers with a total yield of 86%. The diastereomeric dipeptides can be easily separated by flash column chromatography. Acidic cleavage of the derived diastereomers gave both the optically pure (+)‐( R )‐ and (‐)‐( S )‐5‐oxo‐1‐phenyl‐pyrazolidine‐3‐carboxylic acid ((+)‐( R )‐ 2 and (‐)‐( S )‐ 2 ) with a total yield of 94% and 95%, respectively.