SYNTHESIS OF BETA-LINKED DIPORPHYRINS AND THEIR HOMOBIMETALLIC AND HETEROBIMETALLIC COMPLEXES

beta-Meta-and -para-linked diporphyrins have been synthesized from two complementary routes using Suzuki cross-coupling and Adler condensati on. Porphyrin boronate 6 cross couples with beta-monobromoporphyrin 2 to give unsymmetrically substituted porphyrin dimer 7c in high yield, and Adler condensation of beta-formylphenyltetraphenylporphyrins 9b,c with aryl aldehydes yields electronically tunable diporphyrins 7a-e. T he home-and hetero-bimetallic complexes 11a-c have been synthesized. S elective mono-metalation with zinc acetate at the beta-substituted sit e has been found for 7a. The Zn-Co diporphyrin complex 11c undergoes s trong emission quenching compared to that of the diporphyrin 11a and d izinc diporphyrin 11b.