Use this URL to cite or link to this record in EThOS: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.588035
Title: Metathesis routes to carbocyclic frame works
Author: Standen, Patricia E.
Awarding Body: Loughborough University
Current Institution: Loughborough University
Date of Award: 2013
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Abstract:
The addition of allyl magnesium and allyl indium reagents to a key TBS protected norbornenyl building block, synthesised in 6-steps from commercially available 1,1-dimethoxy-2,3,4,5-tetrachlorocyclo-pentadiene, has been achieved providing the syn addition products with high diastereoselectivity. The subsequent exposure of the addition products to metathesis conditions, in the presence of ethylene, then provided cis fused [3.0.3]-carbocycles with very high regioselectivity, via a Ring Rearrangement Metathesis (RRM) transformation. The high level of regioselectivity is due to the rearrangement of the metathesis intermediates to give the more thermodynamically stable product This work has been expanded to include [2.2.2]-bicycles, addition of allyl magnesium and indium reagents to a key bicyclo[2.2.2]oct-5-en-2-one has been achieved, giving both diastereoisomers, separable by chromatography. The subsequent exposure of the addition products to optimised metathesis conditions, then provided cis fused [3.3.1] carbocycles with very high regioselectivity, via a RRM transformation. It was found that two possible cyclisation pathways occur under our reaction conditions; pathway (a) will yield a cis-fused [4.0.3]-carbocycle while pathway (b) will deliver the observed [3.3.1]-carbocycle.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.588035  DOI: Not available
Keywords: Metathesis ; Ring rearrangement metathesis ; Regioselective ; Carbocyclic ; Ottelione ; Ruthenium
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