1. Sustainable Routes to Biodegradable Plastics and Synthetic Biodiesel Fuel – Polymers from CO 2 Objective: UofC: Richard Jordan (PI), Dept. of Chemistry Ben Petro (PD) Tim Lau (GS) ANL:Jeffrey Miller (PI), Chemical Sciences and Engineering Division

2. Carbon Dioxide  Fully oxidized carbon  Anthropogenic carbon ca. 7 Gt per year  Cheap, readily available, sustainable  Potential C1 building block  Thermodynamically stable, chemically unreactive

3. CO 2 as a Chemical Feedstock Bosch-Meiser urea process Salicyclic acid Urea: Fertilizer Chemical intermediate 10 8 tons/y Salicyclic acid: pharma Specialty polycarbonates CH/CO 2 polycarbonate: not commercial

4. Objective: Copolymerize CO 2 with Ethylene Potential payoff: new strategies for catalysis new sustainable routes to useful polymers and fuels new insights to CO 2 activation Target Chemistry: High MW: aliphatic polyesters biodegradable plastics Low MW: synthetic diesel fuel Key Issues: polyolefins aliphatic polyesters polyolefin catalysis design polyolefin catalysts that can incorporate CO 2

5. Polyolefin Plastics Olefin Polymerization Characteristics:tune properties by microstructure control cheap, many applications; 200 x 10 6 tons/y not biodegradable Catalysts: heterogeneous Ziegler-Natta or Cr homogeneous single-site

6. Aliphatic Polyesters PBS Characteristics:properties similar to polyolefins tune properties by microstructure control reactive ester group --> readily biodegradable expensive (5 – 10x PO) PCL

7. Objective: Copolymerize CO 2 with Ethylene Potential payoff: new strategies for catalysis new sustainable routes to useful polymers and fuels new insights to CO 2 activation Target Chemistry: High MW: aliphatic polyesters biodegradable plastics Low MW: synthetic diesel fuel Key Issues: polyolefins aliphatic polyesters polyolefin catalysis design polyolefin catalysts that can incorporate CO 2

8. Olefin Polymerization Catalysis Representative single-site catalysts Chain growth by insertion Design requirements: metal alkyl vacant coord sites activate olefin for Nu - attack

9. Simple Olefin Polymerization Mechanism

10. CO 2 Poisons Olefin Polymerization Catalysts CO 2 insertion Metal carboxylate structures Metallocene deactivation

11. Wacker synthesis of VOAc Nucleophilic Reactivity of Carboxylates Key step Implication for polymerization

12. Wacker synthesis of VOAc Nucleophilic Reactivity of Carboxylates Key step Implication for polymerization

13. New Strategy for Ethylene/CO 2 Copolymerization Key L n M requirements multiple ethylene insertions CO 2 insertion activate ethylene for external Nu - attack no β-O 2 CR elimination tolerant of ester groups incorporate into appropriate binuclear structure Binuclear catalyst

14. New Strategy for Ethylene/CO 2 Copolymerization Key L n M requirements multiple ethylene insertions CO 2 insertion activate ethylene for external Nu - attack no β-O 2 CR elimination tolerant of ester groups incorporate into appropriate binuclear structure Binuclear catalyst

15. New Strategy for Ethylene/CO 2 Copolymerization Key L n M requirements √ multiple ethylene insertions CO 2 insertion activate ethylene for external Nu - attack √ no β-O 2 CR elimination √ tolerant of ester groups √ incorporate into appropriate binuclear structure Binuclear catalyst

16. Discrete Phosphine-sulfonate Pd Catalysts Catalyst Framework Synthesis Structures

17. Polymerizations by (PO)PdMe(py) Catalysts HDPE Tolerance of esters Key Properties: Pd(II), electronic asymmetry, neutral

18. Self-Assembly of Tetranuclear OPO Catalyst

19. Pd1 Pd1A N1 C1 C1A N1A P1A P1 S1A S1 O2 O1 S2 O1A O3 Li1 Li1A O4 O5 O6 O2A O3A C2

20. Towards CO 2 Reactivity CO 2 does not insert Working hypothesis: Pd-Me insufficiently electron rich

21. Design Modifications in Progress Make more electron rich Exploit secondary interactions

22. (PO)PdR catalysts polymerize ethylene to HDPE (PO)PdR catalysts tolerate esters and are resistant to  -O 2 CR elim (OPO)PdR catalysts self-assemble into tetramers with desired Pd--Pd orientation (PO)PdR and (OPO)PdR catalysts do not react with CO 2 Polymers from Ethylene and CO 2 Results to date Current goals Modify (PO)PdR and (OPO)PdR catalysts to enable CO 2 incorp Demonstrate Wacker type reactivity with (PO)PdR and (OPO)PdR More robust self-assembled multinuclear catalysts Ethylene/CO 2 copolymerization

23. Department of Chemistry Let knowledge grow so human life can be enriched