in ethanol Kinetics; const. temp. (40, 50 and 60°C); spectrophotometric monitoring;

in ethanol Kinetics; const. temp. (40, 50 and 60°C); spectrophotometric monitoring;

in ethanol Kinetics; const. temp. (40, 50 and 60°C); spectrophotometric monitoring;

in pyridine; chloroform; acetic acid addition of a filtrated solution of protoporphyrine in pyridine and CHCl3 to a boiling solution of Co(II)-acetate in acetic acid; crystallisation of product at addition of ether;; washing with acetic acid and ether; recrystallisation in pyridine and acetic acid;;