Christian Bruckner, Ross W Boyle, David Dolphin
Meso-Substituted Tripyrrane Compounds, Compositions, and Methods for Making and Using the Same
The invention provides for tripyrrane compounds of the formula
wherein: each Q represents, typically, an alkyl group, cycloalkyl group, aryl group, or a heteroaryl group; and each R represents hydrogen, an alkyl group, alcohol group, or a carbonyl-containing group. Additionally, there arc described methods to prepare such compounds, for example, comprising the steps of: (a) reacting a compound of the formula: Q-CHO or Q-CH(OS)(OS') wherein S and S' are independently lower alkyl, an aryl group containing from 5 to 14 ring atoms, and -(CH2)n-where n =2-4; with a stoichiometric excess of a pyrrole having the formula:
in the presence of a catalytic amount of an acid; (b) removing the unreacted pyrrole or any other solvents used in (a) by evaporation to form a residue; and (c) treating the residue to remove high molecular weight polymeric materials and the corresponding dipyrromethane by-product, leaving the desired compound.