TY - JOUR
T1 - Mono-aluminum, di-magnesium and tri-zinc complexes supported by bisphenolate ligand
T2 - Synthesis, characterization and catalytic studies for ring-opening polymerization of cyclic esters
AU - Li, Chen Yu
AU - Chen, Po Sheng
AU - Hsu, Shi Jie
AU - Lin, Chia Her
AU - Huang, Hsi Ya
AU - Ko, Bao Tsan
N1 - Funding Information:
We gratefully acknowledge the financial support from the National Science Council, Taiwan ( NSC99-2113-M-033-007-MY2 to B.-T. Ko and NSC100- 2632-M-033-001-MY3 to H.-Y. Huang). We also thank Professor Chu-Chieh Lin for valuable discussions.
PY - 2012/10/1
Y1 - 2012/10/1
N2 - Mono-aluminum, di-magnesium and tri-zinc complexes coordinated by a Biphen 2- ligand (Biphen-H 2 = 3,3′-di-tert-butyl-5, 5′,6,6′-tetramethylbiphenyl-2,2′-diol) were synthesized and structurally characterized by X-ray single crystal determinations. The reaction of Biphen-H 2 with AlMe3 (1.0 mol equiv.) in THF produced the tetra-coordinated monomeric aluminum complex [Al(Biphen)Me(THF)] (1), but treatment of Biphen-H 2 with Mg nBu 2 under the same stoichiometric proportion in THF gave the dimeric magnesium complex [Mg(μ-Biphen)(THF)] 2 (2). Tri-zinc [Zn 3(μ, μ-Biphen) 2Et 2(THF) 2] (3) resulted from treatment of Biphen-H 2 with ZnEt 2 (1.5 mol equiv) in THF; it consists of two different kinds of four-coordinated Zn centers. All of metal complexes are coordinated by at least one neutral THF coligand, indicating each metal center can behave as an active site to activate monomers during ring-opening polymerization (ROP). Catalysis for ROP of ε-caprolactone (ε-CL) or β-butyrolactone (β-BL) of complexes 1-3 are investigated, and the comparative studies of ε-CL polymerization are also discussed.
AB - Mono-aluminum, di-magnesium and tri-zinc complexes coordinated by a Biphen 2- ligand (Biphen-H 2 = 3,3′-di-tert-butyl-5, 5′,6,6′-tetramethylbiphenyl-2,2′-diol) were synthesized and structurally characterized by X-ray single crystal determinations. The reaction of Biphen-H 2 with AlMe3 (1.0 mol equiv.) in THF produced the tetra-coordinated monomeric aluminum complex [Al(Biphen)Me(THF)] (1), but treatment of Biphen-H 2 with Mg nBu 2 under the same stoichiometric proportion in THF gave the dimeric magnesium complex [Mg(μ-Biphen)(THF)] 2 (2). Tri-zinc [Zn 3(μ, μ-Biphen) 2Et 2(THF) 2] (3) resulted from treatment of Biphen-H 2 with ZnEt 2 (1.5 mol equiv) in THF; it consists of two different kinds of four-coordinated Zn centers. All of metal complexes are coordinated by at least one neutral THF coligand, indicating each metal center can behave as an active site to activate monomers during ring-opening polymerization (ROP). Catalysis for ROP of ε-caprolactone (ε-CL) or β-butyrolactone (β-BL) of complexes 1-3 are investigated, and the comparative studies of ε-CL polymerization are also discussed.
KW - Bisphenolate
KW - Catalyst
KW - Ring-opening polymerization
KW - Zinc
KW - β-Butyrolactone
KW - ε-Caprolactone
UR - http://www.scopus.com/inward/record.url?scp=84864977283&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84864977283&partnerID=8YFLogxK
U2 - 10.1016/j.jorganchem.2012.06.019
DO - 10.1016/j.jorganchem.2012.06.019
M3 - Article
AN - SCOPUS:84864977283
SN - 0022-328X
VL - 716
SP - 175
EP - 181
JO - Journal of Organometallic Chemistry
JF - Journal of Organometallic Chemistry
ER -