Functionalization of Porphyrins: Mechanistic Insights, Conformational Studies, and Structural Characterizations

The condensation of 3-chloromethylbenzoyl chloride with three atropisomers of meso-5,10,15,20-tetrakis(2-aminophenyl)porphyrin (TAPP) is reported, followed by the reaction of the anion of diethyl malonate to prepare various strapped porphyrins. According to two different geometries of the straps, the resulting preorganization of the hanging ethoxycarbonyl groups is more or less adapted to the coordination of cations such as lanthanides. The conformational study, as well as the X-ray structures of three strapped porphyrins, demonstrate that among the three atropisomers investigated in this work, only two of them lead to strapped porphyrins in which an ethoxycarbonyl group is directed towards…