Cornell University
Library
Cornell UniversityLibrary

eCommons

Help
Log In(current)
  1. Home
  2. Cornell University Graduate School
  3. Cornell Theses and Dissertations
  4. CONTROLLING ARCHITECTURE USING C2-SYMMETRIC CATALYSTS: FROM SMALL MOLECULES TO LARGE POLYMERS

CONTROLLING ARCHITECTURE USING C2-SYMMETRIC CATALYSTS: FROM SMALL MOLECULES TO LARGE POLYMERS

File(s)
Vaccarello_cornellgrad_0058F_10361.pdf (29.72 MB)
Permanent Link(s)
https://doi.org/10.7298/X4F18WW3
https://hdl.handle.net/1813/56722
Collections
Cornell Theses and Dissertations
Author
Vaccarello, David Nicholas
Abstract

My doctoral studies have concentrated on the use of C2-symmetic catalysts to control the three-dimensional construction of molecules. The first half of my thesis focuses on asymmetric addition of phenols into Pd π-allyl complexes. This work was inspired by the natural product, sch202596, an antagonist for the galinin receptor that contains a highly stereogenic and compact carbasurgar structure appended onto a phenol by an allylic aryl-ether bond. A transformation was developed in which racemic allylic oxides underwent a Tsuji-Trost reaction to give diastereomeric π-allyl complexes. Addition of a nucleophile resulted in enantioenriched regioisomers in good yields. We termed this approach allylic oxide regio resolution (AORR). Using this approach, four different carbasurgar natural products were synthesized: streptol, MK7607, cyathiformine B and polyporapyranone G. Additionally, this method was extended to append carbasugar-like molecules onto complex natural products. Furthermore, C2-symmetic catalysts were used to synthesize polymers with stereoregularity, which will be the focus of the second half of my thesis. Utilizing advances in chain walking polymerization, 1-butene was polymerized resulting in a novel isotactic semi-crystalline polymer. The ligand framework and reaction conditions were probed in order to optimized the system, which gave an active catalyst that produced a polymer with few stereo and regioerros. Specifically, it was found that ortho-cumyl groups were necessary to maintain the stereochemical information through the chain walking steps. Additionally reaction conditions were explored and discovered that a reaction temperature of −40 °C and a concentration of approximately 8 M were the optimal conditions. Finally, the use of non-aromatic, high polarity, aprotic solvents proved beneficial.

Date Issued
2017-08-30
Keywords
Materials Science
•
butene
•
carbasugar
•
synthesis
•
Polymer chemistry
•
Polymer
•
Organic chemistry
Committee Chair
Coates, Geoffrey
Committee Member
Lancaster, Kyle M.
Collum, David B.
Degree Discipline
Chemistry and Chemical Biology
Degree Name
Ph. D., Chemistry and Chemical Biology
Degree Level
Doctor of Philosophy
Rights
Attribution-NonCommercial-NoDerivatives 4.0 International
Rights URI
https://creativecommons.org/licenses/by-nc-nd/4.0/
Type
dissertation or thesis

Site Statistics | Help

About eCommons | Policies | Terms of use | Contact Us

copyright © 2002-2026 Cornell University Library | Privacy | Web Accessibility Assistance