Synthesis of novel triarylamine-based dendrimers with N4,N6-dibutyl-1,3,5-triazine-4,6-diamine probe for electron/energy transfers in H-bonded donoracceptordonor triads and as efficient Cu2+ sensorsElectronic supplementary information (ESI) available: Synthesis and characterizations of dendrimers,1H NMR titrations of supramolecular triads and 1H and 13C NMR titrations of sensor response, UVVis and PL spectra of dendrimers and sensor reversibilities. See DOI: 10.1039/c2jm00112h

Two novel highly soluble triarylamine dendrimers TPAD1 and TPAD2 with N 4 ,N 6 -dibutyl-1,3,5-triazine-4,6-diamine probe were synthesized via normal synthetic routes. Both dendrimers ( TPAD1 and TPAD2 ) form H-bonded donoracceptordonor (DAD) supramolecular triads TPAD1-PBI-TPAD1 and TPAD2-PBI-TPAD2 with 3,4,9,10-perylene tetra carboxylic diimide derivative ( PBI ). The presence of multiple H-bonds in the solution state was elucidated by 1 H NMR titrations and IR spectral studies. J-aggregations and electron/energy transfers provided by both dendrimers were verified by UVVis and photoluminescence (PL) titrations with PBI and the particle sizes of supramolecular triads were calculated by X-ray diffraction (XRD) analysis. Similarly, both dendrimers also showed sensitivities towards Cu 2+ in comparison with 19 interfering metal ions, which were evidenced via UVVis and PL titraions in both single and dual metal systems. The maximum detection limit of Cu 2+ ions was determined to be 20 ppm from PL titrations for both dendrimers, and the 1:2 stoichiometry of the complexes formed by both dendrimers ( TPAD1 -Cu 2+ and TPAD2 -Cu 2+ ) were calculated by Job plots based on UVVis absorption titrations. More importantly, the binding mechanism of the 1,3,5-triazine-4,6-diamine probe of both dendrimers was well characterized by 1 H and 13 C NMR titrations ([D 8 ]THF:D 2 O = 2:1 in vol.) and supported by the fluorescence reversibility by adding metal ions and PMDTA sequentially. Two novel triarylamine-based dendrimers TPAD1 and TPAD2 form hydrogen-bonded triads with PBI and also can act as Cu 2+ sensors.