3033-50-9Relevant academic research and scientific papers
Synthesis of optically active α-benzyl paraconic acids and their esters and assignment of their absolute configuration
Berti, Federico,Forzato, Cristina,Furlan, Giada,Nitti, Patrizia,Pitacco, Giuliana,Valentin, Ennio,Zangrando, Ennio
experimental part, p. 313 - 321 (2009/09/05)
The cis- and trans-4-benzylparaconic acids and their ethyl esters were synthesized with high enantiomeric excess by hydrolysis of the corresponding diastereomeric lactonic esters using α-chymotrypsin. Thus, at low conversion values, cis- and trans-4-benzyl-5-oxo-3-tetrahydrofurancarboxylic acids were separately isolated with 99% ee and 92% ee, respectively. Both ethyl ester diastereomers were also obtained in enantiopure form. The absolute configuration of the trans-lactonic acid was assigned by 1H NMR analysis of its ester derivatives with both enantiomers of 1-(9-anthryl)-2,2,2-trifluoroethanol, while that of the cis-lactonic acid was assigned by means of X-ray analysis of a crystalline derivative. The circular dichroism curves of the products obtained are also reported.
