Rochester Institute of Technology RIT Scholar Works Theses Thesis/Dissertation Collections 4-1-2008 The effect of polymer composition and structure on the photo-Fries rearrangement Glen David Labenski Follow this and additional works at: http://scholarworks.rit.edu/theses Recommended Citation Labenski, Glen David, "The effect of polymer composition and structure on the photo-Fries rearrangement" (2008). Thesis. Rochester Institute of Technology. Accessed from This Thesis is brought to you for free and open access by the Thesis/Dissertation Collections at RIT Scholar Works. It has been accepted for inclusion in Theses by an authorized administrator of RIT Scholar Works. For more information, please contact [email protected]. The Effect of Polymer Composition and Structure on the Photo-Fries Rearrangement. Glen David Labenski April 2008 Thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Chemistry. Approved: ___________________________________ Thomas W. Smith (Advisor) ___________________________________ Paul Rosenberg (Department Head) Department of Chemistry Rochester Institute of Technology Rochester, New York 14623-5603 Abstract: The objective of research presented in this thesis is to elucidate the effect of polymer composition and structure on the photo-Fries rearrangement in polymers bearing aryl ester moieties. Towards this end, a systematic study wherein constraint, proximity, and dielectric constant were varied was carried out. This study was enabled by the synthesis of poly(phenylacrylate), poly( p-acetoxystyrene) and copolymers of phenylacrylate or p-acetoxystyrene with ethylacrylate, butylacrylate and 2- hydroxyethylmethacrylate. In addition, siloxane polymers with pendant aryl ester groups were also synthesized. Varying constraint by tethering aryl esters to the polymer backbone at the ester group, tethering aryl esters to the polymer backbone through the aryl group and varying the T g of polymers had no effect on the rate of the photo-Fries rearrangement. The hydration state of hydrophilic copolymers had no effect on conversion but did increase formation of cage escape products and changed the ratio of products formed. Decreasing the proximity of aryl ester units relative to one another lead to increased ultimate conversion in the rearrangement. Altering from a carbon to siloxane polymer backbone may have had an effect on the initial rate of rearrangement but the effect could not be isolated from other variables (proximity and T g). Refractive index changes ( ∆n) which occurred as the polymers underwent rearrangement were also evaluated. Refractive index changes between 0.01 and 0.07 were observed, with the ∆n being controlled in a dose dependent manner. Findings discussed here may be significant in the development of holographic imaging systems, optical data storage devices, waveguides and intra-ocular lens implants where materials capable of significant refractive index modulation are desirable. ii Table of Contents Introduction........................................................................................................................ 1 Objective ..................................................................................................................................... 1 Photochemistry of Aryl Esters ................................................................................................... 1 The photo-Fries Rearrangement in Constrained Media .......................................................... 5 The photo-Fries Rearrangement in Polymers ......................................................................... 12 Utility of the Current Research................................................................................................ 19 Experimental .................................................................................................................... 24 Materials ................................................................................................................................... 24 Instrumentation ........................................................................................................................ 25 Synthesis ................................................................................................................................... 26 Poly(p-acetoxy styrene). .................................................................................................................... 26 Poly(phenyl acrylate). ....................................................................................................................... 27 Poly(phenyl acrylate-co -ethyl acrylate). .......................................................................................... 27 Poly( p-acetoxy styrene-co -butyl acrylate). ...................................................................................... 28 Poly(phenyl acrylate-co -butyl acrylate). ......................................................................................... 29 Poly(phenyl acrylate-co -hydroxyethyl methacrylate). ................................................................... 30 Poly(acetoxy styrene-co -hydroxyethyl methacrylate). ................................................................... 32 Acetoxystyrene functionalized polysiloxane. .................................................................................. 33 Phenyl 3-butenoate functionalized polysiloxane................................................................... 35 Phenyl 3-butenoate. ...................................................................................................................... 35 Hydrosilylation of phenyl 3-butenoate. ...................................................................................... 36 Kinetics Analysis ...................................................................................................................... 37 Variable angle spectroscopic ellipsometry (VASE) Analysis. ................................................. 37 Sensitization of the photo-Fries rearrangement. .................................................................... 38 Synthesis of naphthalene-1-yl benzoate. ......................................................................................... 38 Photo-Fries rearrangement of naphthalene-1-yl benzoate. ........................................................... 39 Results and Discussion .................................................................................................... 39 Synthesis of Polymers .............................................................................................................. 40 Kinetics of the photo-Fries Rearrangement ............................................................................ 42 Constraint. ......................................................................................................................................... 44 iii Proximity. .......................................................................................................................................... 51 Dielectric Constant. ........................................................................................................................... 54 Refractive Index Changes ........................................................................................................ 56 Preliminary Sensitization Experiments ................................................................................... 62 Conclusions and Future Directions ................................................................................ 64 Appendix........................................................................................................................... 65 References ........................................................................................................................ 76 iv List of Figures Figure 1: Acetoxybenzene undergoing the photo-Fries rearrangement........................................................ 2 Figure 2: Detailed mechanism of photo-Fries rearrangement...................................................................... 3 Figure 3: Comparison of thermal and photochemical catalyzed Fries rearrangements............................... 4 Figure 4: Representation of the structure of ZSM-5 zeolite. ......................................................................... 6 Figure 5: Structure of Nafion®. .................................................................................................................... 7 Figure 6: Morphology of water-swollen Nafion®......................................................................................... 7 Figure 7: Structure of β-cyclodextrin............................................................................................................ 8 Figure 8: Rearrangement of β-cyclodextrin naphthyl ester complexes......................................................... 9 Figure 9: Styrene-based amphiphilic homopolymer (polymer A) utilized by Ramamurthy.......................... 11 Figure 10: Photo-Fries rearrangement of polycarbonate........................................................................... 13 Figure 11: Photo-Fries rearrangement of poly(p-acetoxystyrene) and poly(p-formyloxystyrene) ............. 15 Figure 12: Novel photo-Fries active polymers synthesized by Kern........................................................... 16 Figure 13:FT-IR spectra of PAS and poly(bicyclo[2.2.1]hept-5-ene-2-carboxylic acid,