Synthesis and spectral evaluation of 5,10,15,20-tetrakis(3,4-dibenzyloxyphenyl)porphyrin

Porphyrins are of interest in many applications that involve electron transfer and absorption of light, such as solar energy and photodynamic cancer therapy. The newly synthesized 5,10,15,20-tetrakis(3,4-dibenzyloxyphenyl)porphyrin, TDBOPP, was characterized using 1H NMR, 13C NMR, UV-vis and fluorescence spectroscopy and MALDI-TOF/TOF high resolution mass spectrometry. Standard 1H NMR and 13C NMR experiments coupled with nuclear Overhauser effect (NOE) experiments confirmed the structure of the compound. The expected M+ and [M+H]+ ions are observed in the MALDI-TOF/TOF mass spectrum. The UV-vis absorption spectrum of TDBOPP shows a Soret band at 424 nm and three Q bands at 519 nm, 556 nm, and 650 nm with molar absorptivity 3.6×105 cm−1m−1, 1.6×104 cm−1m−1, 1.0×104 cm−1m−1 and 5.3×103 cm−1m−1, respectively. Excitation at 424 nm gives emission at 650 nm. The quantum yield of the porphyrin is 0.11.

Poly(ionic liquid) superabsorbent for polar organic solvents

A simple, polymerized ionic liquid (poly(IL)) based on methylimidazolium cations tethered to a polystyrene backbone exhibits superabsorbent behavior toward polar organic solvents, most notably propylene carbonate (PC) and dimethyl sulfoxide (DMSO), wherein the poly(IL) was observed to swell more than 390 and 200 times (w/w) its original mass, yet absorbs negligible quantities of water, hexanes, and other solvents, many of which were miscible with the IL monomer. Although solubility parameters and dielectric constants are typically used to rationalize such behaviors, we find that poly(IL)-solvent compatibility is most clearly correlated to solvent dipole moment. Poly(IL) superabsorbency is not reliant upon the addition of a cross-linking agent.