Bis(imino)phenoxide complexes of zirconium: synthesis, structural characterization and solvent-free ring-opening polymerization of cyclic esters and lactides

Abstract

Bis(imino)phenoxide complexes of zirconium possess spectacular reactivity towards the solvent-free polymerization of cyclic ester monomers and lactides. Polymerization of lactide is living and the resulting product has exceptionally high number average molecular weights (Mn). Polymerization of β-butyrolactone gives syndiotactic poly(3-hydroxybutyrate) with good Mn and molecular weight distribution (MWD).

Imino(phenoxide) compounds of magnesium: Synthesis, structural characterization, and polymerization studies

“…Such types of arrangements have been previously noticed in our earlier work. 136,137 All the bond lengths and angles tally well with the previous literature reports. [40][41][42][43][44][45][46] Suitable single crystals for X-ray diffraction studies of 11 were grown from toluene at room temperature.…”

“…133 The morphology and structural defects in MgO materials may be altered significantly by controlling the particle size. 134 Our continued interest in study of ring opening polymerization reactions [135][136][137][138][139][140][141][142][143][144][145][146] prompted us to investigate the catalytic behavior of new magnesium complexes. We surmised that controlled hydrolysis of these complexes may provide a facile access to new MgO materials.…”

Zwitterionic Complexes of Group 4 Metal Chlorides Containing a Bis(imino)phenoxide Scaffold: Synthesis, Characterization and Polymerization Studies

“…One of our research interests involves the exploration of new chemistry with group 4 metals . Our recent results highlight the synthesis and use of new alkoxide complexes of group 4 metals containing the bis(imino)phenoxide ligand and their applications as catalysts for the polymerization of cyclic esters, lactides, epoxides and ethylene . The advances of the present catalytic system over related zwitterionic complexes and complexes with other group 4 metals bearing the same coordination environment and related ligands bring into light interesting observations.…”

A new class of MPV type reduction in group 4 alkoxide complexes of salicylaldiminato ligands: Efficient catalysts for the ROP of lactides, epoxides and polymerization of ethylene

“…Group 4 metal complexes of polydentate ancillary ligands have attracted considerable attention during the last few years because of their efficiency as catalyst for ROP of cyclic esters and lactides . In the recent years, our research has been primarily focused on extensive ROP studies using group 4 metal M A N U S C R I P T A C C E P T E D ACCEPTED MANUSCRIPT 5 catalysts [91,[96][97][98][99][100][101][102][103]. However, the development of benign initiators for ROP of lactides to synthesize PLA with narrow MWDs and with controlled stereochemistry remained as an important goal since polymer microstructure plays a significant role on the physical and mechanical properties of PLA.…”