PHOTOCHEMISTRY OF COPPER(II) MACROCYCLIC COMPLEXES BOUND TO POLY(ACRYLIC ACID) - TIME-RESOLVED OBSERVATIONS IN A PICOSECOND-MILLISECOND TIME DOMAIN AND SEQUENTIAL BIPHOTONIC EXCITATIONS

Flash photolysis of Cu(2,3,9,10-Me4-[14]-l,3,8,10-tetraeneN4)2+-poly(acrylate) generates an intermediate, CuIII(2,3,9,10-Me4-[14]-l,3,8,10-tetraeneN4)alkyl, in less than 20 ps. This intermediate decomposes into CuI(2,3,9,10-Me4-[14]-l,3,8,10-tetraeneN4) with a 20-μs lifetime. We have followed, in a millisecond time scale, the disappearance of Cu(2,3,9,10-Me4-[14]-1,3,8,10-tetraeneN4)+, a process that exhibits a kinetics expected for consecutive first- and second-order reactions. The reactions rates are dependent on the number of photochemically generated Cu(I) species per molecule of poly(acrylic acid) but are independent of the solutions' bulk viscosity. Flash irradiations of CuI(2,3,9,10-Me4-[14]-l,3,8,10-tetraeneN4)-poly(acrylate) complexes in aqueous solutions form metastable CuII(ligand radical)-poly(acrylate) complexes. By contrast, CuI(2,3,9,10-Me4-[14]-l,3,8,10-tetraeneN4)+in methanol exhibits no photoreactivity. © 1990, American Chemical Society. All rights reserved.