Katherine Aubrecht

Office: Haberlin 218D

Lab: Haberlin 127

Our research efforts are focused in the areas of synthetic polymer and organic chemistry. Projects we are currently working on are:

Copolymerization of Cyclic Esters with Alkyl Methacrylates.

We are interested in modifying the properties of the biodegradable polyesters polylactide (PLA) and polycaprolactone (PCL) by the incorporation of other functionalized monomers. We are investigating statistical anionic polymerizations of cyclic esters with functionalized methacrylates. This project has received financial support from the ACS-PRF.

 

Synthesis and Characterization of Thermoresponsive Block Copolymers.

We have made thermoresponsive di- and triblock copolymers poly(ethylene oxide)-poly(ethylene oxide-ran-propylene oxide)-poly(lactide) (PEO-(PEO-ran-PPO)-PLA) and poly(ethylene oxide-ran-propylene oxide)-poly(lactide) (PEO-ran-PPO)-PLA. Aqueous solutions of these block copolymers display reversible clouding with changes in temperature. We are currently characterizing the size and shape of the polymeric micelles both above and below the response temperature as well as preparing crosslinkable block copolymers. This project is being done in collaboration with Prof. R. B. Grubbs at Dartmouth College.

Asymmetric Synthesis in Aqueous Media.

A number of carbon carbon bond forming reactions are catalyzed by Lewis acids. Most common Lewis acids such as TiCl4, SnCl4, and BF3 are not stable in water. Recently lanthanide triflates, Ln(OSO2CF3)3, have been shown to be highly active Lewis acids, even in aqueous solution. We would like to carry out asymmetric Lewis acid catalyzed reactions in homogeneous aqueous solution. This will first require the design and synthesis of water-soluble chiral ligands. A careful balance will need to be struck so that the metal cation will bind the ligand, but will not be so sequestered by the ligand that it will not complex with substrates. We will study metal-ligand complexation and then screen a variety of organic reactions for yields and enantioselectivities.