Advances in organic synthesis via micellar catalysis using benign "designer" surfactants
- Degree Grantor:
- University of California, Santa Barbara. Chemistry
- Degree Supervisor:
- Bruce H. Lipshutz
- Place of Publication:
- [Santa Barbara, Calif.]
- University of California, Santa Barbara
- Creation Date:
- Issued Date:
- Organic chemistry
Water chemistry, and
- Dissertations, Academic and Online resources
- Ph.D.--University of California, Santa Barbara, 2015
Focus has been to develop new technologies that are both useful and sustainable to the synthetic community by following the 12 Principles of Green Chemistry. By utilizing micellar catalysis we can facilitate synthetic organic transformations in water at room temperature. This is achieved using nanoparticles derived from tailor-made amphiphiles, designed to both self-aggregate into micellar arrays and enable, at very low concentrations in water, C-C, C-heteroatom, and C-H bond constructions. Through direct quantitation, in the form of comparative E Factors, we document how these methodologies can greatly reduce our dependence on toxic organic solvents (i.e., dipolar aprotic, chlorinated) associated with many of the most commonly used transition metal-catalyzed couplings.
Additionally, given the huge dependence on dipolar, aprotic solvents such as DMF, DMSO, DMAc, and NMP in substitution research, we demonstrate how TPGS-750-M in water can mimic these solvents (e.g., DMF) to perform nucleophilic aromatic substitution reactions (SNAr) using micellar catalysis.
Additionally, Suzuki-Miyaura cross-couplings utilizing N-methyliminodiacetic acid (MIDA) boronate derivatives demonstrate that only water is necessary as the reaction medium when micellar catalysis is employed. This includes reaction setup to product isolation, thereby completely eliminating the use of organic solvents for one of the most utilized organic transformations within the chemistry community.
Lastly, through an attenuation strategy, Suzuki-Miyaura cross-couplings involving challenging 2-pyridyl MIDA boronates have been developed that rely on only palladium as the catalyst. Typically reported conditions include non-catalytic amounts of copper in order for the cross-coupling to be achieved. This strategy sheds insight on how to access, and utilize for synthetic gain, water stable 2-pyridyl boronic acids formed in situ via a slow-release mechanism with particular substituents at the 6-position of the pyridyl core.
- Physical Description:
- 1 online resource (652 pages)
- UCSB electronic theses and dissertations
- Catalog System Number:
- Nicholas Isley, 2015
- In Copyright
- Copyright Holder:
- Nicholas Isley
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