{"term":{"id":"08938","title":"catalyst precursor","longtitle":"IUPAC Gold Book - catalyst precursor","doi":"10.1351\/goldbook.08938","code":"08938","status":"current","synonym":"<em>synonyms<\/em>: initiator (in coordination polymerization), precatalyst (in coordination polymerization)","definitions":[{"id":1,"text":"Coordination compound that by reaction with an activator or cocatalyst provides an active catalyst during initialization of coordination polymerization.","exams":{"1":"Catalyst precursors are certain transition metal or rare-earth metal complexes, such as titanium tetrachloride or bis(cyclopentadienyl)titanium chloride."},"contexts":{"1":"Catalyst precursors are certain transition metal or rare-earth metal complexes, such as titanium tetrachloride or bis(cyclopentadienyl)titanium chloride."},"links":[{"term":"coordination polymerization","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/08995"},{"term":"initialization","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/08956"}],"sources":["PAC, 2022, 94, 1093. 'Terminology for chain polymerization (IUPAC Recommendations 2021)' on page 1116 (https:\/\/doi.org\/10.1515\/pac-2020-1211)"]}],"altoutputs":{"html":"https:\/\/goldbook.iupac.org\/terms\/view\/08938\/html","xml":"https:\/\/goldbook.iupac.org\/terms\/view\/08938\/xml","plain":"https:\/\/goldbook.iupac.org\/terms\/view\/08938\/plain"},"citation":"Citation: 'catalyst precursor' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351\/goldbook.08938","license":"The IUPAC Gold Book is licensed under Creative Commons Attribution-ShareAlike CC BY-SA 4.0 International (https:\/\/creativecommons.org\/licenses\/by-sa\/4.0\/) for individual terms.","collection":"If you are interested in licensing the Gold Book for commercial use, please contact the IUPAC Executive Director at executivedirector@iupac.org .","disclaimer":"The International Union of Pure and Applied Chemistry (IUPAC) is continuously reviewing and, where needed, updating terms in the Compendium of Chemical Terminology (the IUPAC Gold Book). Users of these terms are encouraged to include the version of a term with its use and to check regularly for updates to term definitions that you are using.","accessed":"2026-06-21T23:39:52+00:00"}}