Studies in Aromatic Polyacetylenic Macrocycles

Behr, Omri M (1960) Studies in Aromatic Polyacetylenic Macrocycles. PhD thesis, University of Glasgow.

Abstract

This work may be divided into three closely related sections. The initial problem was to elucidate the structure of an unstable, cyclic polyyne isolated in 1957 by Eglinton and Galbraith in this department. The compound has now been shown to be the cyclic 'dimer' of o-diethynylbenzene, 1,2;7,8-dibenzocyclododeca-l,7-diene-3,5,9,11-tetrayne, and is the first known highly strained acetylene. This unusual structure has been confirmed independently by the X-ray work of Grant and Speakman. It should be noted that the dimers, trimers, tetramers, etc. referred to in this work are not true polymers since two atoms of hydrogen are lost in the oxidative coupling of terminal acetylenes. However, the convenience of this terminology is so great that it has been used throughout the work reported. Transannular effects were found to occur during the reduction of the dimer and several interesting products have been isolated and identified. Second, attempts to synthesise the trimer of o-di-ethynylbenzene, 1,2:7,8:13,14-tribenzocyclooctadeca-1,7,13-triene-3,5,9,11,15,17-hexayne, were not successful, though the course of the work has indicated a possible route to it. During these attempts an unexpected reaction of bromophenyl acetylenes with amines was observed, and some of the products obtained were identified. Finally, a further strained acetylene, the cyclic tetramer of o-diethynylbenzene, 1,2:7,8:13,14:19,20-tetra-benzocyclotetracosa-1,7,13,19-tetraene-3,5,9,11,15,17,21,23-octayne, has been synthesised by an unequivocal route, and its structure verified. Ultraviolet spectra for a hitherto unknown series of aromatic polyynes are presented.

• Item Type: Thesis (PhD)
• Qualification Level: Doctoral
• Keywords: Organic chemistry, Molecular chemistry
• Date of Award: 1960
• Depositing User: Enlighten Team
• Unique ID: glathesis:1960-79366
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 05 Mar 2020 10:35
• Last Modified: 05 Mar 2020 10:35
• URI: https://theses.gla.ac.uk/id/eprint/79366