Enantioselective resolution of 4‐chloromandelic acid by liquid–liquid extraction using 2‐chloro‐N‐carbobenzyloxy‐L‐amino acid. Issue 11 (23rd August 2017)

• Record Type: Journal Article
• Authors: Lu, Ruichen; He, Quan; Feng, Cai; Peng, Yangfeng
• Is Part Of: Chirality. Volume 29:Issue 11(2017)
• Page Start: 708
• Page End: 715
• Publication Date: 2017-08-23
• Subjects: 2‐chloro‐N‐carbobenzyloxy‐L‐amino acid -- 4‐chloromandelic acid -- chiral separation -- liquid–liquid extraction -- N‐(2‐chlorobenzyloxy)‐succinimide -- valine; Chirality -- Periodicals; Pharmaceutical chemistry -- Periodicals; 541.22
• DOI: 10.1002/chir.22738
• Languages: English
• ISSNs: 0899-0042

Abstract

Abstract: A liquid–liquid extraction resolution of 4‐chloro‐mandelic acid (4‐ClMA) was studied by using 2‐chloro‐N‐carbobenzyloxy‐L‐amino acid (2‐Cl‐Z‐AA) as a chiral extractant. Important factors affecting the extraction efficiency were investigated, including the type of chiral extractant, pH value of aqueous phase, initial concentration of chiral extractant in organic phase, initial concentration of 4‐ClMA in aqueous phase, and resolution temperature. It was observed that the concentration of (R)‐4‐ClMA was much higher than that of (S)‐4‐ClMA in organic phase due to a higher stability of the complex formed between (R)‐4‐ClMA and 2‐Cl‐Z‐AA. A separation factor (α) of 3.05 was obtained at 0.02 mol/L 2‐Cl‐Z‐Valine dissolved in dichloromethane, pH of 2.0, concentration of 4‐ClMA of 0.11 mmol/Land T of 296.7K. Abstract :