in coordination polymerization
synonyms: initiator (in coordination polymerization), precatalyst (in coordination polymerization)
https://doi.org/10.1351/goldbook.08938
Coordination compound that by reaction with an activator or cocatalyst provides an active catalyst during initialization of coordination polymerization.
Examples: Catalyst precursors are certain transition metal or rare-earth metal complexes, such as titanium tetrachloride or bis(cyclopentadienyl)titanium chloride.