Highly Active, Productive, and Syndiospecific Yttrium Initiators for Racemic β-Butyrolactone Polymerization
نویسندگان
چکیده
منابع مشابه
Group 3 metal complexes supported by tridentate pyridine- and thiophene-linked bis(naphtholate) ligands: synthesis, structure, and use in stereoselective ring-opening polymerization of racemic lactide and beta-butyrolactone.
Scandium, yttrium and lanthanum amido complexes supported by tridentate bis(ortho-silyl-substituted naphtholate)-donor ligands ({ONO(SiPh3)}(2-) and {ONO(SitBuMe2)}(2-), donor = 2,6-pyridine; {OSO(SiPh3)}(2-), donor = 2,5-thiophene) have been prepared in high yields (72-96%) by reaction of the corresponding pro-ligand {OZO(SiR3)}H(2) and Ln[N(SiHMe(2))(2)](3)(THF)(n) precursor. The solid-state ...
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In this paper we demonstrate the utility of Group 4 metals for the well-controlled and stereoselective (syndiotactic) ring opening polymerization (ROP) of rac-β-butyrolactone (BBL) and their ability to form copolymers.
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Rare-earth complexes are attractive catalyst systems due to their low cost, low toxicity and high reactivity. Modular ligand sets are ideal for complex formation since the steric and electronic properties of the resultant metal complexes can be easily varied. This thesis explores the structure and reactivity of new yttrium amidate complexes, which combine the highly reactive metal with the modu...
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