Synthetic studies toward the preparation of several polypyrrolic macrocycles are described. The majority of the research was directed toward the synthesis of a pentapyrrolic analogue (15) of porphyrin (13). The results were surprising, as a meso-substituted porphyrin (63) was the result. In light of our findings we were able to explain our earlier failures to obtain the pentapyrrole (15) as well as the failures of previous investigators^""*". A sapphyrin (16), the pentapyrrolic analogue of corrole (2), was also prepared, for eventual comparison with our porphyrin analogue (15), and we attempted to insert into 2+ 29 xt a uranyl catxon (UC^ ). The uranyl moiety had been shown to be present in a pentapyrrolic analogue (17) of phthalocyanine (68). By a reaction analogous to that for (17), the synthesis of the five-membered analogue (18) of benzporphyrin (see Scheme 13) was attempted. That macrocycle (18), containing the uranyl ion and being .more porphyrin-like than (17) , would have provided a link between the *superphthalocyanine' (17) and the other macrocycles, (15) and (16). / Science, Faculty of / Chemistry, Department of / Graduate