Chlorinated 2‐hydroxynaphthalenoxazolines: Synthesis, Reaction Mechanism and Fluorescence Properties. Issue 18 (7th November 2016)

• Record Type: Journal Article
• Authors: Barbeiro, Cristiane S.; Vasconcelos, Stanley N. S.; Zukerman‐Schpector, Júlio; Caracelli, Ignez; Pimenta, Daniel C.; Rodrigues, Ana Clara B.; Fernandes, André S.; Correra, Thiago C.; Bastos, Erick L.; Stefani, Hélio A.
• Is Part Of: ChemistrySelect. Volume 1:Issue 18(2016)
• Page Start: 5647
• Page End: 5652
• Publication Date: 2016-11-07
• Subjects: 2-hydroxynaphthalenoxazolines -- One pot synthesis -- Chlorination -- Thionyl chloride -- Fluorescence; Chemistry -- Periodicals; 540.5
• DOI: 10.1002/slct.201601526
• Languages: English
• ISSNs: 2365-6549

Abstract

Abstract: A chlorinated 2‐HNO (2‐hydroxynaphthalenoxazoline) was synthesized by an ultrasound‐assisted coupling reaction between 1‐hydroxy‐2‐naphthoic acid and L‐threonine followed by simultaneous halogenation and cyclization with inversion of configuration using excess SOCl2 . Further functionalization of 2‐HNO led to a small library of slightly fluorescent amides or esters in 55–81 % yields. Quantum chemical calculations combined with high‐resolution mass spectrometry analysis were used to rationalize the mechanism of reaction, and the formation of SCl3 + as an electrophile is proposed. Abstract : 2‐oxazoline was synthesized by an ultrasound‐assisted coupling reaction between 1‐hydroxy‐2‐naphthoic acid and L‐threonine followed by simultaneous halogenation and cyclization with inversion of configuration using excess SOCl2 . Further functionalization of 2‐HNO led to a small library of slightly fluorescent compounds. Quantum chemical calculations combined with high‐resolution mass spectrometry analysis were used to rationalize the mechanism of reaction.