BIROn - Birkbeck Institutional Research Online

Stereoisomerism in pentaerythritol-bridged cyclotriphosphazene tri-spiranes: spiro and ansa 1,3-propanediyldioxy disubstituted derivatives

Aylin, U. and Coles, Simon J. and Davies, David B. and Eaton, R.J. and Hursthouse, Michael B. and Kiliç, A. and Shaw, Robert A. (2005) Stereoisomerism in pentaerythritol-bridged cyclotriphosphazene tri-spiranes: spiro and ansa 1,3-propanediyldioxy disubstituted derivatives. European Journal of Inorganic Chemistry 2005 (6), pp. 1042-1047. ISSN 1434-1948.

[img]
Preview
Text
davies377a.pdf

Download (558Kb) | Preview
Official URL: http://dx.doi.org/10.1002/ejic.200400796

Abstract

Four isomeric products were isolated and purified from the reaction of 1,3-propanediol with the tetra-spirane cyclophosphazene-organophosphate compound (1): viz. the di-monospiro (2a), di-monoansa (2b) and two monospiro-monoansa derivatives (2c) and (2d). It is shown by 31P NMR spectroscopy on addition of a chiral solvating agent (CSA) that both the di-monospiro (2a) and di-monoansa (2b) derivatives are racemates, as expected, whereas no splitting of NMR signals occurred on addition of CSA to solutions of (2c) and (2d). It is found by X-ray crystallography that the two monospiro-monoansa spirane derivatives, (2c) and (2d), are meso diastereoisomers, which represent a new case of the stereochemistry of bis di-substituted cyclophosphazene derivatives of (1). It is also observed from the 31P NMR spectrum of the reaction mixture, supported by the yields of pure compounds, that formation of a spiro group is about 4.5 times more likely than that of an ansa moiety under the conditions of the reaction.

Item Type: Article
Additional Information: Available from http://www.interscience.wiley.com/
Keyword(s) / Subject(s): cyclotriphosphazene derivatives, trispiranes, NMR spectroscopy, tetraspiranes, x-ray diffraction
School or Research Centre: Birkbeck Schools and Research Centres > School of Science > Biological Sciences
Depositing User: Sandra Plummer
Date Deposited: 07 Jun 2006
Last Modified: 17 Apr 2013 12:32
URI: http://eprints.bbk.ac.uk/id/eprint/377

Archive Staff Only (login required)

Edit/View Item Edit/View Item