Work

Deracemization of Quinolonecarboxamides by Dynamic Crystalline Salt Formation and Asymmetric Photoreaction by Using the Frozen Chirality

Year: 2014

Type: article

Abstract: An asymmetric photoreaction by using chirality provided by dynamic chiral salt formation was demonstrated. Crystallization of racemic 2‐quinolone‐3‐carboxamide and 2‐quinolone‐4‐carboxamide with enantiopure L‐dibenzoyltartaric acid led to deracemization and gave high diastereomeric excess values of the crystalline salts in almost quantitative yield. The axial chirality was retained for a long period of time after the salts were dissolved in cooled solvent. The frozen chirality derived from the chiral salts was effectively transferred to the products by using a typical [2+2] photocycloaddition reaction with alkenes.

Source: European Journal of Organic Chemistry

DOI: 10.1002/ejoc.201403056

Authors: Fumitoshi Yagishita, Naoya Takagishi, Hiroki Ishikawa, Yoshio Kasashima, Takashi Mino, Masami Sakamoto

Institutions: Chiba University, Chiba Institute of Technology

Language: English

Topic: Axial and Atropisomeric Chirality Synthesis

Subfield: Organic Chemistry

Field: Chemistry

Domain: Physical Sciences

Open Access status: bronze

Funders: Ministry of Education, Culture, Sports, Science and Technology, Japan Society for the Promotion of Science

Awards: Development of asymmetric generation and amplification phenomenon from achiral substance, G2273825883, Developments of the absolute asymmetric synthesis of optically active derivatives of amino acids with the dynamic preferential crystallization, G4315282766, Generation of Chirality Triggered by Sunlight Irradiation and Development of New Asymmetric Catalysts