Synthesis, Characterization, and Catalytic Studies of Lithium
Complexes: Efficient Initiators for Ring-Opening Polymerization of
l-Lactide
Mao-Lin Hsueh
Bor-Hunn Huang
Jincai Wu
Chu-Chieh Lin
10.1021/ma050600o.s001
https://acs.figshare.com/articles/journal_contribution/Synthesis_Characterization_and_Catalytic_Studies_of_Lithium_Complexes_Efficient_Initiators_for_Ring_Opening_Polymerization_of_l_Lactide/3257176
The reaction of 2,2‘-ethylidenebis(4,6-di-<i>tert</i>-butylphenol) (EDBP-H<sub>2</sub>) with <i><sup>n</sup></i><sup></sup>BuLi in tetrahydrofuran (THF), giving [(EDBP-H)Li(THF)<sub>3</sub>] (<b>1</b>) in high yield. However, the reaction of EDBP-H<sub>2</sub>
with <i><sup>n</sup></i><sup></sup>BuLi in the presence of benzyl alcohol (BnOH) in diethyl ether or tetrahydrofuran produces
compounds [(EDBP-H)Li(BnOH)]<sub>2</sub> (<b>2</b>) and [(EDBP-H)Li(BnOH)(THF)<sub>2</sub>] (<b>3</b>), respectively. Further reaction
of <b>2 </b>with excess of THF produces <b>3</b>. Alternatively, <b>3 </b>can also be prepared by the reaction of benzyl alcohol
with <b>1</b> in toluene. Experimental results show that <b>2 </b>and<b> 3 </b>efficiently initiate the ring-opening
polymerization (ROP) of l-lactide in a controlled fashion, yielding polymers with very narrow polydispersity
indexes in a wide range of monomer-to-initiator ratios. Block copolymers, polystyrene-<i>b</i>-poly(l-lactide),
have also been prepared from the ring-opening polymerization of l-latide catalyzed by <b>3</b> using polystyrene
as a macroinitiator.
2005-11-15 00:00:00
n BuLi
ROP
Experimental results show
polymerization
tetrahydrofuran
THF
benzyl alcohol
polystyrene