Design and Synthesis of Luminescent Bis(isocyanoborato) Rhenate(I) Complexes as a Selective Sensor for Cyanide Anion
Ye-Lan Xiao, Wing‐Kin Chu, Chi‐On Ng, Shun‐Cheung Cheng, Man‐Kit Tse, Shek‐Man Yiu, Chi‐Chiu Ko
Abstract
A series of luminescent bis(isocyanoborato) rhenate(I) phenanthroline complexes with the general formula of cis,trans-[Re(CO)2(CNBR3)2(phen)]K (R = C6F5 and C6H5) have been designed and synthesized. The solutions of these complexes exhibit MLCT phosphorescence. Detailed anion titration study showed that the emission intensity of bis(isocyanotriphenylborato) complex in CH3CN/H2O solution would be significantly decreased in the presence of cyanide anion, while such a change would not be observed in the presence of other anions including F–, Cl–, Br–, I–, OH–, AcO–, N3–, ClO4–, H2PO4–, HSO4–, NO3–, NO2–, IO3–, and SCN–. This provides a new strategy for developing highly selective cyanide luminescent sensors based on isocyanoborato transition metal complexes.