Diversity-based synthesis of nitrogen heterocycles

Austin, Carolyn Ann (2006) Diversity-based synthesis of nitrogen heterocycles. PhD thesis, University of Glasgow.

Abstract

Brief investigations were carried out towards the synthesis of 2,4-disubstituted quinolines and 2,6-disubstituted piperidines using titanium alkylidene chemistry, but these were unsuccessful. A route towards the diversity based stereoselective synthesis of 2-substituted azepane derivatives was explored via titanium alkylidene chemistry. Thioacetals i were reacted with low valent titanium(II) species ii to produce titanium(IV) alkylidenes that were reacted with resin-bound esters iii. Cleavage of the resulting enol ethers led to a small library of amino ketones iv, but reductive amination to give azepanes, remained elusive. However, hydrogenation of the phenylethylamino group in ketones iv gave racemic azepanes v. [diagram] Diversity based synthesis of cyclic imines, both 6 and 7 membered, has been carried out using trityl protected amines vi and vii. Alkylidene formation followed by reaction with a range of resin-bound esters iii gave enol ethers. Cleavage and deprotection under mild acidic conditions followed by treatment with base cyclised aminoketone products to cyclic imines viii and ix. [diagram].

• Item Type: Thesis (PhD)
• Qualification Level: Doctoral
• Keywords: Organic chemistry, heterocyclic, nitrogen, compounds.
• Subjects: Q Science > QD Chemistry
• Colleges/Schools: College of Science and Engineering > School of Chemistry
• Supervisor's Name: Hartley, Dr. Richard
• Date of Award: 2006
• Depositing User: Enlighten Team
• Unique ID: glathesis:2006-73442
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 14 Jun 2019 08:56
• Last Modified: 20 May 2021 18:32
• URI: http://theses.gla.ac.uk/id/eprint/73442