Abstract
A strategy to synthesize branched polyketoesters from the carbonylative polymerization of bifunctional α,ω-alkenols such as 10-undecen-1-ol is presented. This strategy hinges on the competitive application of two related catalytic manifolds, alternating alkene/CO copolymerization, and alkene hydroesterification, which share a common metal acyl intermediate. Small molecule model studies of cationic Pd-catalyzed alkene carbonylation in the presence of alcohols demonstrate that the relative rates of ketone formation (through alternating alkene/CO insertion) and ester formation (through metal acyl alcoholysis) can be tuned across a wide range through judicious bis(phosphine) ligand design. Carbonylative polymerization of 10-undecen-1-ol with a (dppp(3,5-CF3)4)Pd(OTs)2catalyst (dppp(3,5-CF3)4= 1,3-bis[bis[3,5-bis(trifluoromethyl)phenyl]-phosphino]propane) led to the formation of high molecular weight polyketoesters with intermediate dispersity (Mn> 20,000 g/mol, D = 2.6) and a ketone/ester microstructure ratio of approximately 1:2. In these polymerization reactions, deploying electron-deficient bis(phosphines) to suppress deleterious alkene isomerization was the key to accessing the high molecular weight polymer. Further, terpolymerization reactions of 1-hexene/10-undecen-1-ol/CO or 1-fluoro-10-undecene/10-undecen-1-ol/CO by (dppp(3,5-CF3)4)Pd(OTs)2were also successful. This proof of concept polymerization unlocks access to tunable polymer microstructures without extensive postpolymerization treatment.
Original language | English (US) |
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Pages (from-to) | 14629-14636 |
Number of pages | 8 |
Journal | ACS Catalysis |
Volume | 12 |
Issue number | 23 |
DOIs | |
State | Published - Dec 2 2022 |
Bibliographical note
Publisher Copyright:© 2022 American Chemical Society. All rights reserved.
Keywords
- 10-undecen-1-ol
- carbonylation
- hydroesterification
- polyester
- polyketoester
- polyketone