The Design and Synthesis of Novel Molecular Systems to Study the Relationship between Structure and Reactivity in Organic and Organosilicon Compounds

My programme of research is carried out in collaboration with Dr Peter Taylor and involves several aspects.

These include the use of multinuclear NMR spectroscopy to examine molecular motions, reaction dynamics and molecular structure; the synthesis and study of extracoordinate silicon compounds; the use of novel organosilicon compounds in organic synthesis and the synthesis of highly ordered polymeric silicones.

• In the mechanistic area, systems have been developed that enable the geometrical and mechanistic changes in substitution reactions in solution to be studied quantitatively [Refs 1,2 below] or mapped in a semi-quantitative way by analyzing the NMR spectra of a series of model compounds [3-7].
• Much of my current work involves the synthesis of so-called 'octopus molecules' - particularly those derived from the cubic cage octasilsesquioxane H₈(SiO_3/2)₈ (as shown above). These molecules have novel geometry, with a spherical core surrounded by the eight molecular arms. Within the group we are undertaking an extensive programme of synthesis, characterization and investigation of the physical and chemical properties of these compounds. [8-10]
• Organosilicon reagents are an indispensable part of the armoury of organic chemists. Attempts are being made by a variety of means to introduce successful chiral organosilicon reagents. This is challenging work and some interesting chemistry is emerging. [11]

In addition to the current work, future plans include a programme concerned with the exploitation of extracoordination at silicon (and other elements) in the preparation of supramolecular assemblies.

I am happy to discuss any aspect of my work and supply reprints of my publications on request.

Selected Publications:

1. "Nucleophile-assisted racemisation of halosilanes; an alternative pathway involving halide exchange", A.R. Bassindale, J. C-Y. Lau and P.G. Taylor; J. Organomet. Chem.;
   • 341, 1988, 213.
   • 490, 1995, 75.
   • 499, 1995, 137.
   
   
2. "The Mechanism of Nucleophilic Attack at Silicon" A. R. Bassindale and P.G. Taylor, Chapter 9 in The Chemistry of Organosilicon Compounds, Volume 2; Z. Rappoport and Y. Apeloig (eds.), Wiley, 1998.



3. "An NMR method for mapping reactions in solution"; A.R. Bassindale and M. Borbaruah; J. Chem. Soc. Chem. Commun.; 1991, 1499.



4. "A map of nucleophilic substitution at silicon in solution"; A.R. Bassindale and M. Borbaruah; J. Chem. Soc. Chem. Commun.; 1991, 1501.



5. "Bis-halo N,N-bisdimethylsilylmethylacetamides as dynamic probes for the effect of coordination on reactivity at silicon"; A.R. Bassindale and M. Borbaruah; J. Chem. Soc. Chem. Commun.; 1993, 352.



6. "Modelling nucleophilic substitution at silicon in solution, using hypervalent silicon compounds based on 2-pyridones"; A. R. Bassindale, M. Borbaruah, S.J. Glynn, D.J. Parker, P.G. Taylor; J. Chem. Soc., Perkin Trans 2; 1999, 2099.



7. "The X-ray structure of a protonated hypervalent silanol"; A. Bassindale, D.J. Parker, P.G. Taylor, N. Auner, B. Herrschaft, Chem. Comm.; 2000, 565.



8. "Siloxane and Hydrocarbon Octopus Molecules with Silsesquioxane Cores"; A.R. Bassindale and T.E. Gentle, J. Mat. Chem.; 3, 1993, 1319.



9. "Effect of Catalyst on Regioselectivity and Vinyl/H Exchange on Silicon in the Hydrosilylation of Vinylsiloxanes by T₈ Hydrogen silsesquioxane"; A.R. Bassindale and T.E. Gentle; J. Inorg. Organometal. Polym.; 5, 1995, 281.



10. "Octopus Molecules Based on Silsesquioxane cores"; A. Bassindale et al; Chapter 13 in 'Taylor-Made Silicon-Oxygen Compounds: From Molecules to Materials; R Corriu and P Jutzi (eds.), Vieweg, 1996.



11. "The synthesis of 2-trialkylsilylaziridines from vinyltrialkylsilanes or the reaction of alpha-chloro-alpha-silyl carbanions with imines"; A. Bassindale, P.A. Kyle, M-C. Soobramanien, P.G. Taylor, J. Chem. Soc., Perkin Trans. 1, 7, 2000, 1173.

Other Interests:

While several others in the research group are football fanatics, my particular passion is cricket both as a sport to play (usually for the Open University) and as a spectator sport if time or energy is lacking!