Jump to main content
Jump to site search

Issue 33, 2017
Previous Article Next Article

Ring opening polymerisation of lactide with uranium(IV) and cerium(IV) phosphinoaryloxide complexes

Author affiliations

Abstract

The C3-symmetric uranium(IV) and cerium(IV) complexes Me3SiOM(OArP)3, M = U (1), Ce (2), OArP = OC6H2-6-tBu-4-Me-2-PPh2, have been prepared and the difference between these 4f and 5f congeners as initiators for the ring opening polymerisation (ROP) of L-lactide is compared. The poorly controlled reactivity of the homoleptic analogue U(OArP)4 (3) demonstrates the importance of the M-OSiMe3 initiating group. The incorporation of a nickel atom in 1 to form the U–Ni heterobimetallic complex Me3SiOU(OArP)3Ni (4) may be the first example of the use of the inverse trans influence to switch the reactivity of a complex. This would imply the formation of the U–Ni bond strengthens the U–OSiMe3 bond to such an extent that the ROP catalysis is switched off. Changing the conditions to immortal polymerisation dramatically increases polymerisation rates, and switches the order, with the Ce complex now faster than the U analogue, suggesting ligand protonolysis to afford a more open coordination sphere. For the ROP of rac-lactide, uranium complex 1 promotes heterotacticity at the highest levels of stereocontrol yet reported for an actinide complex.

Graphical abstract: Ring opening polymerisation of lactide with uranium(iv) and cerium(iv) phosphinoaryloxide complexes

Back to tab navigation

Supplementary files

Publication details

The article was received on 14 Jun 2017, accepted on 14 Jul 2017 and first published on 02 Aug 2017


Article type: Communication
DOI: 10.1039/C7DT02167D
Citation: Dalton Trans., 2017,46, 10786-10790
  • Open access: Creative Commons BY-NC license
  •   Request permissions

    Ring opening polymerisation of lactide with uranium(IV) and cerium(IV) phosphinoaryloxide complexes

    F. Sinclair, J. A. Hlina, J. A. L. Wells, M. P. Shaver and P. L. Arnold, Dalton Trans., 2017, 46, 10786
    DOI: 10.1039/C7DT02167D

    This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence. Material from this article can be used in other publications provided that the correct acknowledgement is given with the reproduced material and it is not used for commercial purposes.

    Reproduced material should be attributed as follows:

    • For reproduction of material from NJC:
      [Original citation] - Published by The Royal Society of Chemistry (RSC) on behalf of the Centre National de la Recherche Scientifique (CNRS) and the RSC.
    • For reproduction of material from PCCP:
      [Original citation] - Published by the PCCP Owner Societies.
    • For reproduction of material from PPS:
      [Original citation] - Published by The Royal Society of Chemistry (RSC) on behalf of the European Society for Photobiology, the European Photochemistry Association, and RSC.
    • For reproduction of material from all other RSC journals:
      [Original citation] - Published by The Royal Society of Chemistry.

    Information about reproducing material from RSC articles with different licences is available on our Permission Requests page.

Search articles by author

Spotlight

Advertisements