My thesis is composed of four themed sections: (1) The introduction reviews the Prins reaction, focusing mainly on the Prins condensation-cyclisation of homoallylic alcohols with aldehydes giving substituted tetrahydropyrans. This section also briefly reviews the Prins reaction giving dihydropyrans and the aza-Prins reaction giving piperidines and dihydropiperidines. (2) The results and discussion section details the author's own work and is further divided into two parts. The first part describes the synthesis of novel homoallylic alcohols and bis-homoallylic alcohols from Pd(O)/ln(O) mediated three and five component cascade reactions respectively. The reaction is shown to be catalytic in both Pd(O) and In(O) and the efficiency of the 2,2'-bithiophene as additive is clearly demonstrated and explained. The reaction conditions have been optimised and include a safer and environmentally friendly solvent, a reduction in reaction time (from 16 to 2h) and an increase in reaction yield (from 40-42 to 59- 94%). The software package Spartan" is employed to predict likely conformations of the products. The second part describes the synthesis of 2,4,4,6-substituted tetrahydropyrans using statistically optimised Prins reaction conditions. Excellent control of stereoselectivity at C(4) of the tetrahydropyran is achieved through solvent choice, which allows either epimer to be accessed, with solvent polarizability the key factor. (3) The robotics and statistical techniques section details the statistical techniques Principal Component Analysis (PCA) and Design of Experiments (DoE), the author's own robotic system setup and the unique design of a new reaction vessel for three-phase (solid, liquid, and gas) reaction systems. The second part details the design, robotic setup and statistical analysis of the authors output. (4) The thesis concludes with full experimental details of the authors own work, together with the appropriate physical, spectroscopic and analytical data for all new compounds.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:551229 |
| Date | January 2011 |
| Creators | Chaudhry, Sofia Javid |
| Publisher | University of Leeds |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
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