Organic Poster Presentations

A synthesis for tetrazole functionality from amide precursor

Maillet, Robert

  • Robert Maillet, Chang-Chun Ling*
  • Organization: University of Calgary
  • Funding: University of Calgary, NSERC

Abstract: The synthesis of tetrazole ring systems has been an area of interest for some time, there have been several purposed methods for their synthesis, however never one which resulted from an amide or imidate precursor species. Recent discovery by Y. Cai et. all showed the 5-membered aromatic ring could be formed in this manner. This reaction, and these conditions were tested with multiple substrates and 3 new tetrazole species were identified and characterized. It was also discovered that a key factor to the success of this reaction may be the presence of an extremely hydrophobic or bulky group at either the R1 or R2 position.


Attempts at One-Bond Homologation in the Synthesis of Dinitrile Ligands

Martell, Jon

  • Jon Martell, Grace Strom*, Kristopher J. Ooms*
  • Organization: The King’s University College
  • Funding: King’s University College

Abstract: The effects of ligand flexibility in metal-organic frameworks is poorly understood in coordination chemistry. Compounds 1-3 have been proposed as ligands that would provide a direct comparison of a structurally rigid aliphatic dinitrile ligand (1) to ones with an increase in conformational flexibility (2 and 3). The synthesis of ligand 3 is the focus of this investigation. A proposed strategy for the synthesis of ligand 3 involves the one-bond homologation of synthetic precursors to ligand 2. The Arnt-Eistert reaction and Kowalski homologation were explored as synthetic means to achieve this goal. An alternate synthetic strategy into ligand 3 will also be discussed. Key steps in this synthesis involving the conversion of dialdehyde 4 to diene 5 followed by hydroboration as illustrated in Scheme 1.


Synthesis of 13C-labelled methylphloracetophenone

Norquay, Amy

  • Amy Norquay, John L. Sorensen*
  • Organization: University of Manitoba
  • Funding: NSERC - USRA

Abstract: Lichens are the result of a symbiosis between fungal and algal partners, and have proven to be a rich source of biologically active natural products. The lichen secondary metabolite usnic acid is of particular interest, due to its wide array of activities, notably anti-bacterial, anti-viral, anti-inflammatory and potentially anti-cancer properties. Ethylphloracetophenone is a key intermediate in the biosynthesis of usnic acid; however the oxidative enzyme involved in that transformation has not yet been characterized. One of our goals is to isolate the enzyme responsible for this oxidation from lichen tissue. The synthesis of methylphloracetophenone is a crucial part of this endeavour. Here we describe the synthesis of methylphloracetophenone by the methylation of commercially available trihydroxyacetophenone with methyl iodide. Our optimized procedure was used to synthesize 13C-labelled methylphloracetophenone, which will be used for bioassay guided identification of the oxidative enzyme.

Exploration of Novel Boronic Acid Protecting Groups

Zhang, Chenxi

  • Chenxi (Tracy) Zhang, Sam Mothana*, Dennis Hall*
  • Organization: University of Alberta
  • Funding: NSERC

Abstract: Boronic acids are versatile compounds that are essential in many important reactions. However, they tend to decompose easily in atmospheric and aqueous conditions, as well as form anhydrous boroxine trimers. To prevent these properties from hindering reactions and lowering yields, free boronic acids can be made more stable with protecting groups. Many potential protecting groups were synthesized and reacted with p-tolylboronic acid under a range of conditions to give various adducts. One particularly promising adduct was a boronate ester formed with citramalic acid and p-tolylboronic acid, which gave high yields under mild reaction conditions. This adduct was put through competitive Suzuki-Miyaura coupling reactions with a free boronic acid, and was seen to remain stable under anhydrous reaction conditions via HNMR mass spectroscopy.