One-pot efficient synthesis of pyrrolylBODIPY dyes from pyrrole and acyl chloride

Min Zhang, Erhong Hao, Yajun Xu, Shengzhou Zhang, Hongnian Zhu, Qi Wang, Changjiang Yu, Lijuan Jiao
2012 RSC Advances  
Scheme S1. Initial synthesis of BODIPY 1a and 3-pyrrolylBODIPY 2a via pyrrole and acetyl chloride in dichloromethane at room temperature General: Reagents and solvents were used as received from commercial suppliers unless noted otherwise. All reactions were performed in oven-dried or flame-dried glassware unless otherwise stated, and were monitored by TLC using 0.25 mm silica gel plates with UV indicator (60F-254). 1 H and 13 C NMR were recorded on a 300 MHz NMR spectrometer at room
more » ... at room temperature. Chemical shifts (δ) are given in ppm relative to CDCl 3 (7.26 ppm for 1 H and 77 ppm for 13 C) or to internal TMS. High-resolution mass spectra (HRMS) were obtained using APCI-TOF in positive mode. UV-visible absorption spectra and Fluorescence emission spectra were recorded on a commercial spectrophotometer (190-1100 nm scan range, Shimadzu UV-2450 and Hitachi F-4500). Relative fluorescence quantum efficiencies of BODIPY derivatives were obtained by comparing the areas under the corrected emission spectrum of the test sample in various solvents with fluorescein (Φ = 0.90 in 0.1 N NaOH aqueous solution) or Rhodamin B (Φ = 0.49 in EtOH). 1 Non-degassed, spectroscopic grade solvents and a 10 mm quartz cuvette were used. Dilute solutions (0.01<A<0.05) were used to minimize the reabsorption effects. Quantum yields were determined using the following equation 2 : Where Φ S stands for the reported quantum yield of the standard, I stands for the integrated emission spectra, A stands for the absorbance at the excitation wavelength and n stands for the refractive index of the solvent being used. X subscript stands for the test Electronic Supplementary Material (ESI) for RSC Advances This journal is © The Royal Society of Chemistry 2012 S3 sample, and S subscript stands for the standard. Fluorescence lifetimes were measured on a combined steady-state lifetime fluorescence spectrometer and the fluorescence lifetimes were obtained from deconvolution and distribution lifetime analysis. Details of the instrumentation and experimental procedures used have been described elsewhere. 3 When the fluorescence decays were single exponential, the rate constants of radiative (k f ) and nonradiative (k nr ) deactivation were calculated from the measured fluorescence quantum yield and fluorescence lifetime using the following equation: k f = /τ and k nr = (1-)/τ. Crystals of BODIPYs 1a, 2a and 2i suitable for X-ray analysis were obtained by slow evaporation of their dichloromethane solutions. The vial containing this solution was placed, loosely capped, to promote the crystallization. The structure was solved by the direct method using the SHELXS-974 program and refined by the least-squares method on F 2 , SHELXL-97, 4 incorporated in SHELXTL V5.10. 5 CCDC-881436 (1a), 881437 (2a), and 881438 (2i) contain the supplementary crystallographic data for this paper. These data can be obtained free of charge from The Cambridge Crystallographic Data Centre via www.ccdc.cam.ac.uk/data_request/cif. Fluorescence Imaging: Human gastric cancer SGC7901 cells were cultured in Dulbecco's Modified Eagle Medium (DMEM) supplemented with 10% fetal bovine serum, penicillin (100 U/ml), streptomycin sulfate (100 μg/ml), and maintained at 37°C with 5% CO 2 in a humidified incubator. One day before imaging, cells were seeded in 6well flat-bottomed plates in an atmosphere of 5% CO 2 , 95% air at 37°C. Fluorescence imaging of intracellular dyes was observed under OLYMPUS-IX71 inverted fluorescence microscope and imaged using FITC channel or TRITC channel. The cells were treated with 10 μM of dyes in culture media for 30 min at 37°C with 5% CO 2 in a humidified incubator. Fluorescence imaging was then carried out after washing the cells with the Electronic Supplementary Material (ESI) for RSC Advances This journal is
doi:10.1039/c2ra22203e fatcat:ag623gpjijfnniuvzer77tn7ga