Investigation of macrocyclisation routes to 1,4,7-triazacyclononanes : efficient syntheses from 1,2-ditosylamides

Stones, G. and Tripoli, Régis and McDavid, Colin L. and Roux-Duplatre, Kewin and Kennedy, A.R. and Sherrington, D.C. and Gibson, C.L. (2008) Investigation of macrocyclisation routes to 1,4,7-triazacyclononanes : efficient syntheses from 1,2-ditosylamides. Organic and Biomolecular Chemistry, 6 (2). pp. 374-384. ISSN 1477-0520

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    Abstract

    Two routes to the synthesis of a cyclohexyl-fused 1,4,7-triazacyclononane involving macrocyclisations of tosamides have been investigated. In the first approach, using a classic Richman-Atkins-type cyclisation of a cyclohexyl-substituted 1,4,7-tritosamide with ethylene glycol ditosylate, afforded the cyclohexyl-fused 1,4,7-triazacyclononane in 5.86% overall yield in four steps. The second, more concise, approach involving the macrocyclisation of trans-cyclohexane-1,2-ditosamide with the tritosyl derivative of diethanolamine initially gave poor yields (< 25%). The well-documented problems with efficiencies in macrocyclisations using 1,2-ditosamides led to the use of a wider range of 1,2-ditosamides including ethane-1,2-ditosamide and propane-1,2-ditosamide. These extended studies led to the development of an efficient macrocyclisation protocol using lithium hydride. This new method afforded 1,4,7-tritosyl-1,4,7-triazacyclononanes in good yield (57-90%) from 1,2-ditosamides in a single step. These efficient methods were then applied to the preparation of a chiral cyclohexyl-fused 1,4,7-tritosyl-1,4,7-triazacyclononane (65-70%). This key chiral intermediate was then converted into a copper(II) complex following detosylation and N-methylation. The resulting chiral copper(II) complex catalysed the aziridination of styrene but it did so in a racemic fashion.

    Author(s):Stones, G., Tripoli, Régis, McDavid, Colin L., Roux-Duplatre, Kewin, Kennedy, A.R. ORCID logoORCID: https://orcid.org/0000-0003-3652-6015, Sherrington, D.C. and Gibson, C.L. ORCID logoORCID: https://orcid.org/0000-0003-4948-1266
    Item type:Article
    ID code:19843
    Keywords:chiral aziridines, crystal structure, dynamic behavior, model complexes, ring closure, ligands, Chemistry, Biochemistry, Organic Chemistry, Physical and Theoretical Chemistry
    Subjects:Science > Chemistry
    Department:Faculty of Science > Pure and Applied Chemistry
    Depositing user: Strathprints Administrator
    Date deposited:04 Jun 2010 13:49
    Last modified:03 Jan 2020 07:21
    URI:https://strathprints.strath.ac.uk/id/eprint/19843
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