Molecular Structure of a Hydridoniobocene Complex [Nb(eta(5)-C5H4SiMe3)(2)(H)(3)] and Its Use as Catalyst for the Ring-Opening Polymerization of Cyclic Esters

作者：Alonso Moreno Carlos; Antinolo Antonio^*; Garcia Martinez Joaquin C; Garcia Yuste Santiago; Lopez Solera Isabel; Otero Antonio; Perez Flores Juan C; Tercero Morales Maria T

来源：European Journal of Inorganic Chemistry, 2012, 2012(7): 1139-1144.

DOI：10.1002/ejic.201101263

• Metallocenes
• Ring-opening polymerization
• Hydride ligands
• Niobium
• Lactones

The second polyhydridoniobocene complex that was characterized by X-ray diffraction is reported. On the basis of H-H distances and H-Nb-H angles, [Nb(eta(5)-C5H4SiMe3)(2)(H)(3)] (1) is classified as a %26quot;compressed hydride%26quot;. Compound 1 acts as an efficient single-component initiator for the ring-opening polymerization of epsilon-caprolactone and delta-valerolactone. epsilon-Caprolactone and delta-valerolactone are both polymerized within a few hours to yield high-to-medium-molecular-weight polymers with medium to broad polydispersities. Polymer end-group analysis showed that the polymerization proceeds through a coordination-insertion mechanism based on the cleavage of the ring between the oxygen atom and the acyl carbon atom.

• 出版日期2012-3