Collman has contributed to several aspects of transition metal chemistry, as documented in over 366
scientific papers. In the 1960s his group demonstrated that certain metal
acetylacetonates undergo
Friedel-Crafts-like reactions, indicating that these chelate rings have aromatic character. In the area of organometallic chemistry, through reviews as well as original research, his group popularized the
oxidative addition reaction, leading to the discovery of new low-valent complexes including Ru(CO)3(PPh3)2 and IrCl(N2)(PPh3)2.
Collman's reagent, Na2Fe(CO)4, prepared in his laboratories, enables certain C-C coupling reactions in
organic synthesis. He coauthored an influential textbook,
Principles and Applications of Organotransition Metal Chemistry, that went through three editions. He popularized the use of
tetraphenylporphyrin as a
biomimetic ligand for exploring the structure and function of
myoglobin,
cytochrome P450, and
cytochrome oxidase. ==Awards and honors==