A novel fluorescence resonance energy transfer (FRET) system based on the interaction of an AIE luminogen (tetraphenylethene, TPE) and BODIPY derivative as the host and guest, respectively, was disclosed. This FRET system worked well for mimicking a light harvesting system with highly energy transfer efficiency up to 93% from aggregation-induced emission to BODIPY emission and shows excellent tolerance to acidic and basic environments.

•A new ratiometric chemodosimeter 1 was developed for recognizing Cu2+ efficiently.•Chemodosimeter 1 works well within a wide range pH and physiological conditions.•1 shows high selectivity and low detection limitation (0.2 μM) in aqueous medium.•1 can be successfully utilized in fluorescent imaging in living cells for Cu2+ detection.A new BODIPY derivative bearing hydrazone and hydrazide moieties was developed as an efficient dual-channel ratiometric fluorescence chemodosimeter 1 for Cu2+ in neutral aqueous medium via Cu2+-mediated hydrolysis of CN bond in hydrazone unit. Confocal microscopy experiments have demonstrated that chemodosimeter 1 could also be used in live cells for the fast detection of Cu2+.

•1,3,5-Trisubstituted pyrazoles were synthesized efficiently with excellent regioselectivity.•Reaction was carried out at mild condition: room temperature.•Reaction was tolerated for many substrates with a wide scope of functional groups.•Reaction was carried out in good yield: the yields of most products were higher than 80%.•A plausible reaction mechanism was proposed.A new practical and efficient synthesis of 1,3,5-trisubstituted pyrazoles has been developed by reacting of hydrazonoyl halides with β-oxophosphonates under mild conditions in good yields with excellent regioselectivity. This process employs an addition–elimination sequence. Wide scope, functional group compatibility has been established.Figure optionsDownload full-size imageDownload as PowerPoint slide

•A colorimetric and ‘turn-on’ fluorescent chemodosimeter for Cu2+ was developed.•Detection of Cu2+ in aqueous solution successfully at low detection limitation (0.2 μM), significant fluorescence enhancement (1340-fold).•The probe was successfully utilized in detecting Cu2+ in living cells.A new BODIPY (4,4-difluoro-1,3,5,7-tetramethyl-4-bora-3a,4a-diaza-s-indacene)-based colorimetric and fluorescent chemodosimeter 1 has been designed and synthesized. Specific turn-on fluorescence response of 1 for Cu2+ was investigated in CH3CN–H2O (1:1, v/v) solution, which can be deduced to a reaction of Cu2+ promoted selectively hydrolysis of CN bond to generate formyl-BODIPY. The chemodosimeter 1 can selectively recognize Cu2+ rather than other metal ions in aqueous solution. Confocal fluorescence imaging of cells for detecting Cu2+ in vivo was carried out successfully. The favorable features of chemodosimeter 1 toward Cu2+ include significant fluorescence enhancement (1340-fold), high selectivity, and low detection limit (0.2 μM).

•A new fluorescent chemosensor for Fe3+ was developed.•Detection of Fe3+ in aqueous solution (THF/H2O) successfully based on aggregation-induced emission mechanism.•High selectivity and sensitivity with low detection limitation (0.7 μM).•The recognizing mechanism was investigated through fluorescence titration and 1H NMR titration.A new tetraphenylethylene (TPE)-based sensor M1 bearing double 2-methylpyridyl-2-methylthiophenylamino units linked with triazole moieties was reported. Both UV–vis and fluorescence spectroscopic studies demonstrated that M1 was highly sensitive and selective toward Fe3+ over other metal ions in THF/H2O solution based on the aggregation-induced emission quenching mechanism. The lowest detection limit of M1 for Fe3+ is 0.7 μM. The detailed fluorescent titration study suggested that the binding stoichiometry of the M1–Fe3+ complex was 1:2, and the structure between M1 and the Fe3+ complex was confirmed by the 1H NMR titration.

A practical, convenient, and highly efficient mono- and diiodination of 1,3,5,7-tetramethyl BODIPY derivatives was achieved by using IOAc as the iodination reagent which was generated in situ from the mixture of phenyliodine(III) diactate with iodine. The iodinated reactions were performed smoothly to give the mono- or diiodination products in good to excellent yields.