Presenter: Kai Cao Supervisor: Prof. Xiaosong Wang Department: Chemistry Synthesis and Self-Assembly of Main-Chain Metal Carbonyl Organometallic Macromolecules (MCMCOMs) by Migration Insertion Polymerization (MIP)

Outline  Background of metal carbonyl organometallic macromolecules  Synthesis of iron-carbonyl organometallic macromolecules (PFpP) by migration insertion polymerization (MIP)  Self-assembly of homopolymer PFpP in aqueous solution  Summary  Acknowledgement  Background of metal carbonyl organometallic macromolecules  Synthesis of iron-carbonyl organometallic macromolecules (PFpP) by migration insertion polymerization (MIP)  Self-assembly of homopolymer PFpP in aqueous solution  Summary  Acknowledgement

Materials application of metal carbonyl organometallic macromolecules (1) Magnetic materials (3) CO delivery (2) Resist for electron beam lithography G.N. Tew et al, Nat.Commun. 2011, 2, 482 W.Y. Chan et al, J. Am. Chem. Soc. 2005, 127 U. Hasegawa et al, J. Am. Chem. Soc. 2010, 132

Synthesis of main-chain metal carbonyl organometallic macromolecules (MCMCOMs) 1)MCMCOMs containing Metal-Metal bond The polymer is photochemically degradable as the metal-metal bond is weak 2) MCMCOMs containing main group element Isolation of the monomer is difficult Cross-linking occurred for the polymer Isolation of the monomer is difficult Cross-linking occurred for the polymer D. R. Tyler, Coord. Chem. Rev. 2003, 246, 291. K. H. Pannell et al, J. Am. Chem. Soc. 2004, 126, Cao, K.; Wang, X. Macromol. Rapid Commun. 2015, 36,

5 Development of new polymerization ? Interesting property Difficulty in synthesis Air stable, soluble main chain metal carbonyl organometallic macromolecules Air stable, soluble main chain metal carbonyl organometallic macromolecules Development of new polymerization technique is required

Adeyemi, O. G.; N. J. Coville.Organometallics (11): Migration insertion reaction (MIR) MIR can be used to link organometallic units into a macromolecular chain structure A-B type bifunctional monomer 6 FpP PFpP

Synthesis and characterization of FpP 7 31 P NMRX-ray diffraction Yield: 60 % Fp anion Cao, K.; Wang, X. Organometallics 2014, 33,

1 H and 13 C NMR spectra for FpP in DMSO-d 6 c a+b DMSO H2OH2O Cp Ph bc a DMSO Cp Ph CO ppm 1 H NMR 13 C NMR FpP was successfully synthesized

Cyclization reaction of FpP in dilute solution 9

Entry a Temp. ( o C)DMSO b M n (g/mol)PDI c d DMSO3000 d DMSO25700 d 1.73 Bulk polymerization of FpP a Polymerization time was 20 hours. b DMSO (ca. 5% by weight) was added. c end group analysis. Suppress the cyclization reactions Table 1. Effects of temperature and DMSO on the bulk polymerization of FpP

Polymerization of FpP at 110 o C in bulk Adeyemi, O. G.; Coville, N. J. Organometallics 2003, 22, Decarbonylation happened at 120 o C in bulk

1 H NMR and 31 PNMR spectra for PFpP with DP= H NMR 31 P NMR

13 Thermal properties of PFpP TGA DSC T g = 100 o C The resulting polymer is thermally stable up to 180 o C and has a T g of 100 o C Wang, X. S.; Cao, K. J. Am. Chem. Soc. 2013, 135,

Thermal responsive behavior of PFpP in DMSO 14 High molecular weight PFpP exhibited a UCST in DMSO Cao, K.; Wang, X. Chem. Commun, 2014, 50(70),

15 Self-assembly of macromolecules Block copolymer Amphiphilic homopolymer Mai Y, Eisenberg A. Chem. Soc. Rev. 2012;41(18):5969 Y. Zhu, L. Liu and J. Du, Macromolecules, 2012, 46(1), 194 Metal containing block copolymer Ren, Lixia, Chuanbing Tang. J. Am. Chem. Soc.2010, 132, 8874  Amphiphilicity  Crystallization  Electrostatic interaction  Hydrogen bonding  Amphiphilicity  Crystallization  Electrostatic interaction  Hydrogen bonding

16 PFpP in hydrophobic Insoluble in H 2 O PFpP in THF H2OH2O THF was removed by N 2 bubbling 0.1 mg/ml 0.05 mg/ml Self-assembly of PFpP in water R h = 77 nm PDI = 0.03 ζ = mV R h = 74 nm PDI = 0.03 ζ = mV

4 nm Investigation of the morphology of PFpP colloids RhRh RgRg R g /R h Light scattering measurement (0.009 mg/mL) 2. TEM measurement bc 200 kV TEM dark field Cryo-TEM a Cao, K. Wang, X. Macromolecules. 2015, 48,

18 Diameter: 113 nm Height: 27 nm diameter-to height ratio: 4.0 Diameter: 113 nm Height: 27 nm diameter-to height ratio: 4.0 Investigation of the morphology of PFpP colloids (0.1 mg/mL) 3. AFM measurement Light scattering, TEM and AFM analysis confirmed that the PFpP colloids are vesicles.

FT-IR of PFpP The polarized COs exert a strong water carbonyl interaction, which drives the self-assembly of PFpP The polarized COs exert a strong water carbonyl interaction, which drives the self-assembly of PFpP J. P. Bibler, A. Wojcicki, Inorganic Chemistry 1966, 5, cm -1 PFpP in THF PFpP solid cm -1

Water carbonyl interaction 20 Hydration of the carbonyl groups is reason for the stability of the colloids

21 Encapsulation of hydrophilic molecules in PFpP colloids Hydrophilic molecules H2OH2O Remove the unencapsulated hydrophilic molecules by dialysis 2000 g/mol Branco, Monica CJoel P. Schneider. Acta biomaterialia, 2009: 817

nm a bc AFM analysis of PFpP colloids with encapsulated PEG Diameter: 113 nm Height: 63 nm diameter-to height ratio: 1.8 Diameter: 113 nm Height: 63 nm diameter-to height ratio: 1.8 PFpP colloids are less deformed when filled with guest molecules

Summary 23  Bifunctional monomer CpFe(CO) 2 (CH 2 ) 3 PPh 2 (FpP) was synthesized and characterized using single crystal X-ray diffraction, FT-IR and NMR spectroscopies.  Effects of temperature and DMSO on the polymerization have been investigated. Relatively higher molecular weight PFpP with M n =25700 g/mol was prepared in bulk at 105 o C in the presence of DMSO (5 wt%). The high molecular weight PFpP exhibited a UCST in DMSO.

Summary  Hydrophobic homopolymer PFpP can self-assemble into stable and uniform vesicles in water. FT-IR analysis indicates that hydration of the carbonyl groups is a supramolecular driving force. The morphology of the nanoparticles was proved using light scattering and TEM measurement. 24

Acknowledgement Supervisor: Prof. Xiaosong Wang Committee member: Prof. Mario Gauthier Prof. Boxin Zhao Prof. Sonny Lee

Thank you !