The thermal and anionic amino-Cope rearrangement of suitably functionalised 3-amino-1,5-hexadienes could potentially constitute a powerful tool for the stereoselective synthesis of highly functionalised acyclic or cyclic systems. [Illustration omitted.] Incorporation of β-aminoalcohol auxiliaries into the diene enabled high diastereoselectivity to be obtained during the 1,2-addition of the allyl Grignard reagent to α,β-unsaturated imines. Asymmetric anionic amino-Cope rearrangement of the diastereoisomerically pure 3-amino-1,5-diene substrates furnished the target aldehyde in good yield and with high levels of asymmetric induction (up to 94% e.e.). The aldehyde obtained was used as a non-racemic starting material to synthesise small heterocycles, with high levels of diastereoselectivity in some cases, providing a high yielding route to some important chiral building blocks. The successful formation of both tetrahydropyrans and lactones without any apparent loss of chirality was achieved and provided a background for investigation into the synthesis of piperidines, which could lead to a plausible route to biologically significant aza-sugars.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:247901 |
| Date | January 1996 |
| Creators | Baird, Robert Duncan |
| Publisher | Loughborough University |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | https://dspace.lboro.ac.uk/2134/33967 |
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