Rationalizing the Reactivity of Mixed Allyl Rare-Earth Borohydride Complexes with DFT Studies
Open Access
Abstract
The reactivity of rare-earth complexes RE(BH4)2(C3H5)(THF)x (RE = La, Nd, Sm, Y, Sc) toward the Ring-Opening Polymerization (ROP) of ε-caprolactone (ε-CL) was rationalized by Density Functional Theory (DFT) calculations. Even if the polymerization reaction can be initiated by both RE-(BH4) and RE-allyl bonds, experimental investigations have shown that the initiation via the borohydride ligand was favored, as no allyl group could be detected at the chain-end of the resulting polymers. DFT studies could confirm these observations, as it was highlighted that even if the activation barriers are both accessible, the allyl group is not active for the ROP of ε-CL due to the formation of a highly stable intermediate that disfavors the subsequent ring-opening.Keywords
This publication has 34 references indexed in Scilit:
- Theoretical Study on the Ring-Opening Polymerization of ε-Caprolactone by [YMeX(THF)5]+ with X = BH4, NMe2Organometallics, 2011
- Cationic Allyl Complexes of the Rare‐Earth Metals: Synthesis, Structural Characterization, and 1,3‐Butadiene Polymerization CatalysisChemistry – A European Journal, 2009
- Cationic Methyl Complexes of the Rare-Earth Metals: An Experimental and Computational Study on Synthesis, Structure, and ReactivityInorganic Chemistry, 2008
- Cationic rare-earth metal bis(tetrahydridoborato) complexes: direct synthesis, structure and ring-opening polymerisation activity toward cyclic estersDalton Transactions, 2008
- Synthesis of multiblock poly(l-lactide)-co-poly(ε-caprolactone) from hydroxy-telechelic prepolymers prepared by using neodymium tetrahydroborateReactive and Functional Polymers, 2007
- Lanthanide Borohydride Complexes of Bulky Guanidinate Ligands [(Me3Si)2NC(N‐Cy)2]2Ln(μ‐BH4)2Li(THF)2 (Ln = Nd, Sm, Yb): Synthesis, Structure and Catalytic Activity in Lactide PolymerizationEuropean Journal of Inorganic Chemistry, 2007
- Organometallic Early Lanthanide Clusters: Syntheses and X-ray Structures of New Monocyclopentadienyl ComplexesInorganic Chemistry, 2004
- New Bulky Allyl Complexes of Lanthanide Metals: Role of Alkali-Metal Cations in Controlling Solid-State and Solution Assemblies in PrecatalystsOrganometallics, 2003
- Erratum: Generalized gradient approximation for the exchange-correlation hole of a many-electron system [Phys. Rev. B54, 16 533 (1996)]Physical Review B, 1998
- Intermolecular interactions from a natural bond orbital, donor-acceptor viewpointChemical Reviews, 1988