Decomposition of tree leaf litter and formation of soil organic matter

Abstract

his PhD thesis describes the laboratory scale preparation of a number of indenes
and indoles, specifically the methodologies applied for the synthesis of these.
Firstly the generation of 1,2-dichlorocyclopropenes from tetrachlorocyclopropanes
upon reaction with 1.3 molecular equivalents of methyl lithium, which ring open to
vinylcarbenes at low temperatures, were quenched with several carbonyl containing
compounds to form a new carbon-oxygen bond. A series of 1,2-dichloro-3-phenylcyclopropenes
were synthesised, which ring opened to the vinylcarbene and trap
intramolecularly with the benzene ring to give a mixture of two indene regioisomers.
The benzene ring substituents was studied as to the affect on this reaction.
The second half of the thesis examined methods of indole synthesis. Firstly the Heck
reaction with the coupling of iodoaniline and alkynes gave limited results and
involved harsh conditions and lengthy reaction times. The Okuro modification of the
copper catalysed Castro reaction was found to give an indole intermediate cleanly in
low yield with short reaction times. These alkynes were then easily cyclised to
indoles in quantitative yield. The Sonogashira reaction gave the same intermediates
in higher yield through quick reaction at room temperature.
A modified Madelung reaction was used to convert a wide range of functionalised
toluidines to indoles with short reaction times through deprotonation with tert-butyl
lithium. A range of quenching reagents were developed to effectively insert alkyl and
aryl groups onto the 2-position of the indole.

Date of Award	Jul 2004
Original language	English
Awarding Institution	University of Wales, Bangor
Supervisor	Davey Jones (Supervisor)