title: Greatly Enhanced Fluorescence by Increasing the Structural Rigidity of an Imine: Enantioselective Recognition of 1,2-Cyclohexanediamine by a Chiral Aldehyde.
abstract: An aldehyde that is not fluorescent responsive toward a chiral diamine has been converted to a sensitive fluorescence enhancement sensor through incorporation of an additional hydrogen bonding unit to increase the structural rigidity of the reaction product of the aldehyde with the diamine. This new chiral aldehyde is synthesized in one step from the reaction of (S)-3-formylBINOL with salicyl chloride. When treated with trans-1,2-cyclohexanediamine in ethanol, it shows greatly enhanced fluorescence at λ=410 nm with good enantioselectivity. NMR and mass spectroscopic methods are used to investigate the reaction of the chiral aldehyde with the diamine. This study has revealed a two-stage reaction mechanism including a fast imine formation and a slow ester cleavage.
authors.affiliation: Key Laboratory of Green Chemistry and Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu, 610064, P. R. China.
authors.forename: Yimang
authors.initials: Y
authors.lastname: Xu
authors.affiliation: Key Laboratory of Green Chemistry and Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu, 610064, P. R. China. yushanshan@scu.edu.cn.
authors.forename: Shanshan
authors.initials: S
authors.lastname: Yu
authors.affiliation: Key Laboratory of Green Chemistry and Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu, 610064, P. R. China.
authors.forename: Qi
authors.initials: Q
authors.lastname: Chen
authors.affiliation: Key Laboratory of Green Chemistry and Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu, 610064, P. R. China.
authors.forename: Xuemin
authors.initials: X
authors.lastname: Chen
authors.affiliation: Key Laboratory of Green Chemistry and Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu, 610064, P. R. China.
authors.forename: Meng
authors.initials: M
authors.lastname: Xiao
authors.affiliation: Key Laboratory of Green Chemistry and Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu, 610064, P. R. China.
authors.forename: Liming
authors.initials: L
authors.lastname: Chen
authors.affiliation: Key Laboratory of Green Chemistry and Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu, 610064, P. R. China. xqyu@scu.edu.cn.
authors.forename: Xiaoqi
authors.initials: X
authors.lastname: Yu
authors.affiliation: Humanwell Healthcare (Group) Co., LTD., 666 Gaoxin Road, East High-Tech Development Zone, Wuhan, Hubei, 430075, P. R. China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Xu
authors.affiliation: Key Laboratory of Green Chemistry and Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu, 610064, P. R. China. lp6n@virginia.edu.|Department of Chemistry, University of Virginia, McCormick Rd, Charlottesville, VA, 22904, USA. lp6n@virginia.edu.
authors.forename: Lin
authors.initials: L
authors.lastname: Pu
keywords: BINOL; chiral amine; chiral recognition; fluorescence sensor; imine