Fullerene-templated synthesis of a cyclic porphyrin trimer using olefin metathesis.

An olefination approach to the construction of covalently linked cyclic metalloporphyrin trimers is presented using fullerenes such as C(60) or C(70) as a template. Yields of the trimer approach 60%. In the absence of a template, the major product is the cyclic dimer (50% yield) with only a small amount of trimer (<10%) formed, indicating this is a template-directed approach.