One-step synthesis of dipyrromethanes in water

In this communication we describe the first results of an efficient synthesis of [beta]-free-dipyrromethanes in water. This new method affords very pure products in moderate to high yields, using a cheap, non-toxic, environment friendly solvent, in a one-step procedure from pyrrole and carbonyl compounds, needing little or no work up procedures.http://www.sciencedirect.com/science/article/B6THS-48FBYP9-W/1/58e27991754d6f7646fd28ad555927b

Electric polarization effects on the electronic spectral shift of centrosymmetric compounds

The classic dielectric dipolar Onsager model was extended to include quadrupolar interactions between solute molecules and solvents with different polarities. A multiparametric solvatochromic expression, based on the point quadrupole moment inside a spherical cavity embedded in a dielectric continuum, is applied to centrosymmetric sulfonamide porphyrins, zinc tetraphenyl porphyrin, squaraine and 9,10-dicyanoanthracene, in order to account for the quadrupolar polarization effect of solute molecules. The reaction field polarity functions created respectively by dipole and quadrupole moments are compared and found to be linearly correlated.http://www.sciencedirect.com/science/article/B6TFM-4BWMWP4-3/1/7e83fc1afe1cdc78a74cf6fe9ffed39