Corrins kinetic template reactions

Numerous kinetic template reactions have been employed in the formation of porphyrins, corrins and phthalocyanins (see Section 61.1.3). The most instructive examples from a mechanistic point of view are those employed by Eschenmoser and his coworkers in the formation of corrins and... 

More direct attempts by Eschenmoser and his group to build up corrins at the desired oxidation level have unearthed a wealth of kinetic template cyclization processes. These have in turn developed into techniques which can now be applied to porphinoid compounds as well. A brief summary of the types of template cyclization reactions is relevant here. 

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