title: Structurally well-defined group 4 metal complexes as initiators for the ring-opening polymerization of lactide monomers.
abstract: Polylactide (PLA) is an attractive polymeric material due to its origin from annually renewable resources and its biodegradability. The ring-opening polymerization (ROP) of lactide initiated by Lewis acidic and oxophilic metal-based catalysts constitutes the method of choice to access PLA in a controlled and stereoselective manner. The design and synthesis of ligand-supported metal complexes to act as effective ROP initiators of lactide monomers have been the subject of numerous investigations over the past decades. In view of their oxophilic nature, well-defined group 4 metal complexes supported by polydentate supporting ligands have appeared as active initiators for lactide ROP. This perspective summarizes various classes of structurally well-defined group 4 metal initiators developed for lactide ROP. It also provides observed trends regarding their catalytic performance. Whenever appropriate and possible, catalyst structure-ROP performance (i.e. activity, control and stereoselectivity) relationships are rationalized.
authors.affiliation: Institute of Inorganic Chemistry, RWTH Aachen University, Landoltweg 1, D-52056 Aachen, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Sauer
authors.forename: Andreas
authors.initials: A
authors.lastname: Kapelski
authors.forename: Christophe
authors.initials: C
authors.lastname: Fliedel
authors.forename: Samuel
authors.initials: S
authors.lastname: Dagorne
authors.forename: Moshe
authors.initials: M
authors.lastname: Kol
authors.forename: Jun
authors.initials: J
authors.lastname: Okuda
mesh_terms: D015394:Molecular Structure; D009942:Organometallic Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D011091:Polyesters / Q000138:chemical synthesis* / Q000737:chemistry; D058105:Polymerization; D028561:Transition Elements / Q000737:chemistry*
chemical_list: D009942:Organometallic Compounds; D011091:Polyesters; D028561:Transition Elements; C033616:poly(lactide)