Replacing Cu(II)Br<sub>2</sub> with Me<sub>6</sub>‑TREN in Biphasic Cu(0)/TREN Catalyzed SET-LRP Reveals the
Mixed-Ligand Effect
Xiaojing Feng
Devendra S. Maurya
Nabil Bensabeh
Adrian Moreno
Takahiro Oh
Yuqing Luo
Ja̅nis Lejnieks
Marina Galià
Yoshiko Miura
Michael J. Monteiro
Gerard Lligadas
Virgil Percec
10.1021/acs.biomac.9b01282.s001
https://acs.figshare.com/articles/journal_contribution/Replacing_Cu_II_Br_sub_2_sub_with_Me_sub_6_sub_TREN_in_Biphasic_Cu_0_TREN_Catalyzed_SET-LRP_Reveals_the_Mixed-Ligand_Effect/9971375
The
mixed-ligand system consisting of tris(2-aminoethyl)amine (TREN)
and tris(2-dimethylaminoethyl)amine (Me<sub>6</sub>-TREN) during the
Cu(0) wire-catalyzed single electron transfer-living radical polymerization
(SET-LRP) of methyl acrylate (MA) in “programmed” biphasic
mixtures of the dipolar aprotic solvents NMP, DMF, and DMAc with H<sub>2</sub>O is reported. Kinetic and chain end analysis studies by NMR
and MALDI-TOF before and after thio-bromo “click” reaction
demonstrated that Me<sub>6</sub>-TREN complements and makes the less
expensive TREN a very efficient ligand in the absence of externally
added Cu(II)Br<sub>2</sub>. Statistical analysis of the kinetic data
together with control experiments demonstrated that this mixed-ligand
effect enhanced the apparent rate constant of propagation, monomer
conversion, and molecular weight control. The most efficient effect
was observed at a 1/1 molar ratio between these two ligands, suggesting
that in addition to a fast exchange between the two ligands, a new
single dynamic ligand generated by hydrogen bonding may be responsible
for the mixed ligand observed.
2019-10-11 14:49:51
monomer conversion
TREN
mixed-ligand system
DMF
mixed-ligand effect
MALDI-TOF
Mixed-Ligand Effect
chain end analysis studies
MA
SET-LRP
Statistical analysis
methyl acrylate
weight control
H 2 O
electron transfer-living
NMR
Cu
dipolar aprotic solvents NMP
tris
control experiments