Synthesis of a BINOL-Based C3 Symmetric Schiff Base and Its Fluorescence Response to Zn2+

A novel C-3 symmetric 1,1'-bi-2-naphthol-based Schiff base (R,R,R)-6 has been synthesized which shows highly selective fluorescence enhancement with Zn2+ among 21 metal cations examined. Its sensitivity and selectivity are found to be greater than other related C-2 (1) and C-1 [(R)-9] symmetric compounds in the fluorescent recognition of Zn2+. The mechanistic study reveals that the selective fluorescence enhancement of the probe can be attributed to the formation of a unimolecular multidentate 6-coordinated Zn2+ complex.

Automated summary

A novel C-3 symmetric Schiff base compound (R,R,R)-6 has been synthesized and exhibits highly selective fluorescence enhancement with Zn2+ among 21 tested metal cations. Its sensitivity and selectivity surpass other related C-2 (1) and C-1 [(R)-9] symmetric compounds in fluorescent recognition of Zn2+. Mechanistic study suggests that the selective fluorescence enhancement is attributed to the formation of a unimolecular multidentate 6-coordinated Zn2+ complex.