Synthesis and complexing properties of phosphorylated imines of 8-formyl-7-hydroxycoumarin

Condensation of o-(diphenylthiophosphoryl)aniline with 8-formyl-7-hydroxy-4-methylcoumarin yields the Schiff base capable of acting as a tridentate monoanionic ligand upon coordination with the ReI and PdII ions. The corresponding palladium complex shows high catalytic activity in the Suzuki cross-couplings of aryl bromides with phenylboronic acid. The analogous P(O)-substituted ligand was not isolated in the pure form; however, using template-assisted method, its κ3-O,N,O-zinc complex was synthesized; this complex is luminescent in the MeCN solution at 20 ℃.