Phosphasalen yttrium complexes: Highly active and stereoselective initiators for lactide polymerization

Thi-Phuong-Anh Cao, Antoine Buchard, Xavier F. Le Goff, Audrey Auffrant, Charlotte K. Williams

Research output: Contribution to journalArticle

84 Citations (Scopus)

Abstract

Preparation and characterization of three yttrium alkoxide complexes with new phosphasalen ligands are reported. The phosphasalens are analogues of the well-known salen ligands but with iminophosphorane donors replacing the imine functionality. The three yttrium alkoxide complexes show mono- and dinuclear structures in the solid state, depending on the substituents on the ligand. The new ligands and complexes are characterized using multinuclear NMR spectroscopy, mass spectrometry, elemental analysis, and single-crystal X-ray diffraction experiments. The complexes are all rapid initiators for lactide polymerization; they show excellent polymerization control on addition of exogeneous alcohol. The mononuclear complex shows extremely rapid rates and a high degree of stereocontrol in rac-lactide polymerization, yielding heterotactic PLA (Ps of 0.9). The phosphasalens are, therefore, excellent ligands for lactide ring-opening polymerization catalysis showing superior rates and stereocontrol versus salen ligands, which may be related to their excellent donating ability and the high degrees of steric protection they can confer.
Original languageEnglish
Pages (from-to)2157-2169
Number of pages13
JournalInorganic Chemistry
Volume51
Issue number4
DOIs
Publication statusPublished - 7 Feb 2012

Fingerprint

Yttrium
initiators
yttrium
polymerization
Polymerization
Ligands
ligands
alkoxides
Imines
Ring opening polymerization
imines
Catalysis
Nuclear magnetic resonance spectroscopy
catalysis
Mass spectrometry
dilactide
alcohols
mass spectroscopy
Alcohols
Single crystals

Cite this

Phosphasalen yttrium complexes: Highly active and stereoselective initiators for lactide polymerization. / Cao, Thi-Phuong-Anh; Buchard, Antoine; Le Goff, Xavier F.; Auffrant, Audrey; Williams, Charlotte K.

In: Inorganic Chemistry, Vol. 51, No. 4, 07.02.2012, p. 2157-2169.

Research output: Contribution to journalArticle

Cao, Thi-Phuong-Anh ; Buchard, Antoine ; Le Goff, Xavier F. ; Auffrant, Audrey ; Williams, Charlotte K. / Phosphasalen yttrium complexes: Highly active and stereoselective initiators for lactide polymerization. In: Inorganic Chemistry. 2012 ; Vol. 51, No. 4. pp. 2157-2169.
@article{e6ef1cd381384712b2ff0109fb394a3b,
title = "Phosphasalen yttrium complexes: Highly active and stereoselective initiators for lactide polymerization",
abstract = "Preparation and characterization of three yttrium alkoxide complexes with new phosphasalen ligands are reported. The phosphasalens are analogues of the well-known salen ligands but with iminophosphorane donors replacing the imine functionality. The three yttrium alkoxide complexes show mono- and dinuclear structures in the solid state, depending on the substituents on the ligand. The new ligands and complexes are characterized using multinuclear NMR spectroscopy, mass spectrometry, elemental analysis, and single-crystal X-ray diffraction experiments. The complexes are all rapid initiators for lactide polymerization; they show excellent polymerization control on addition of exogeneous alcohol. The mononuclear complex shows extremely rapid rates and a high degree of stereocontrol in rac-lactide polymerization, yielding heterotactic PLA (Ps of 0.9). The phosphasalens are, therefore, excellent ligands for lactide ring-opening polymerization catalysis showing superior rates and stereocontrol versus salen ligands, which may be related to their excellent donating ability and the high degrees of steric protection they can confer.",
author = "Thi-Phuong-Anh Cao and Antoine Buchard and {Le Goff}, {Xavier F.} and Audrey Auffrant and Williams, {Charlotte K.}",
year = "2012",
month = "2",
day = "7",
doi = "10.1021/ic202015z",
language = "English",
volume = "51",
pages = "2157--2169",
journal = "Inorganic Chemistry",
issn = "0020-1669",
publisher = "American Chemical Society",
number = "4",

}

TY - JOUR

T1 - Phosphasalen yttrium complexes: Highly active and stereoselective initiators for lactide polymerization

AU - Cao, Thi-Phuong-Anh

AU - Buchard, Antoine

AU - Le Goff, Xavier F.

AU - Auffrant, Audrey

AU - Williams, Charlotte K.

PY - 2012/2/7

Y1 - 2012/2/7

N2 - Preparation and characterization of three yttrium alkoxide complexes with new phosphasalen ligands are reported. The phosphasalens are analogues of the well-known salen ligands but with iminophosphorane donors replacing the imine functionality. The three yttrium alkoxide complexes show mono- and dinuclear structures in the solid state, depending on the substituents on the ligand. The new ligands and complexes are characterized using multinuclear NMR spectroscopy, mass spectrometry, elemental analysis, and single-crystal X-ray diffraction experiments. The complexes are all rapid initiators for lactide polymerization; they show excellent polymerization control on addition of exogeneous alcohol. The mononuclear complex shows extremely rapid rates and a high degree of stereocontrol in rac-lactide polymerization, yielding heterotactic PLA (Ps of 0.9). The phosphasalens are, therefore, excellent ligands for lactide ring-opening polymerization catalysis showing superior rates and stereocontrol versus salen ligands, which may be related to their excellent donating ability and the high degrees of steric protection they can confer.

AB - Preparation and characterization of three yttrium alkoxide complexes with new phosphasalen ligands are reported. The phosphasalens are analogues of the well-known salen ligands but with iminophosphorane donors replacing the imine functionality. The three yttrium alkoxide complexes show mono- and dinuclear structures in the solid state, depending on the substituents on the ligand. The new ligands and complexes are characterized using multinuclear NMR spectroscopy, mass spectrometry, elemental analysis, and single-crystal X-ray diffraction experiments. The complexes are all rapid initiators for lactide polymerization; they show excellent polymerization control on addition of exogeneous alcohol. The mononuclear complex shows extremely rapid rates and a high degree of stereocontrol in rac-lactide polymerization, yielding heterotactic PLA (Ps of 0.9). The phosphasalens are, therefore, excellent ligands for lactide ring-opening polymerization catalysis showing superior rates and stereocontrol versus salen ligands, which may be related to their excellent donating ability and the high degrees of steric protection they can confer.

UR - http://www.scopus.com/inward/record.url?scp=84857700566&partnerID=8YFLogxK

UR - http://dx.doi.org/10.1021/ic202015z

U2 - 10.1021/ic202015z

DO - 10.1021/ic202015z

M3 - Article

VL - 51

SP - 2157

EP - 2169

JO - Inorganic Chemistry

JF - Inorganic Chemistry

SN - 0020-1669

IS - 4

ER -