Chalcomer assembly of optical chemosensors for selective Cu2+ and Ni2+ ion recognitionElectronic supplementary information (ESI) available. See DOI: 10.1039/c4ra14329a

• Main Authors: Singh, Gurjaspreet, Singh, Jandeep, Mangat, Satinderpal Singh, Singh, Jasbhinder, Rani, Sunita
• Format: Article
• Language: English
• ISSN: 2046-2069
• DOI: 10.1039/c4ra14329a

The o -, m - and p -isomeric units of chalconyl triazole-based, caged organosilicon complexes were efficiently synthesized and explored for their cationic chemosensing activities. The UV-vis spectral studies performed show considerable variations in absorption spectra and molar absorptivity constant. The recognition studies display efficient sensing for the o -isomer of chalcone-linked 1,2,3-triazole silatrane (CTSI) 1-3 , which act as dual-ion fluorescent sensors towards Cu 2+ and Ni 2+ ions. This preference of o -isomers ( CTSI 1-3 ) over m - and p -isomers ( CTSI 4-9 ) in quenching is due to specific 'fitting in' of the coordination sphere available for ion binding. Further, the exceptional activity of CTSI 8 to exclusively sense Ni 2+ ions differs from the other studied quenching response patterns, acting via a 'turn-on' fluorescence response. The variation of pH and temperature on the chemosensing behavior of CTSI 1-3 led us to optimize conditions for quenching studies. Moreover, competitive quenching studies confirm the feebly enhanced selectivity for Cu 2+ over Ni 2+ ions. Stern-Volmer constant ( K SV ) for all active isomers show comparative quenching response towards both cationic species. This is the first the time that organosilicon complexes are used to actively sense Cu 2+ and Ni 2+ ions using water as part of the solvent mixture. The o -, m - and p -isomeric units of chalconyl triazole-based, caged organosilicon complexes were efficiently synthesized and explored for their cationic chemosensing activities.