The use of cyclic sulfamidates as pseudo-alkyl halides in Sp3 -based cross-coupling chemistry has been studied and two approaches were explored. The first approach involved a transition metal-mediated cross-coupling of cyclic sulfamidates, including studies into the oxidative addition step of the catalytic cycle. Various transition metal catalysts (palladium, nickel and iron) and nucleophiles (zinc, boron, magnesium and tin reagents) were investigated. After extensive screening, the desired cross-coupling was achieved under palladium-catalysed Suzuki-Miyaura conditions, albeit in a low yield (20%) and with poor mass recovery. The second approach, via enantiomerically pure f3- and y-aminoalkyl boronic esters, required development of efficient conditions for borylation of cyclic sulfamidates. A range of known and novel 1,2- and 1,3-cyclic sulfamidates was synthesised and subjected to the optimised borylation conditions to determine the scope of this transformation. Mechanism of the copper-catalysed borylation process was also explored, together with the utility of boronic esters in sp3 _Sp2 and Sp3 _sp3 cross-coupling reactions. Aminoalkyl boronic esters (from borylation of cyclic sulfamidates) were also assessed as possible substrates for Matteson homologation. After extensive screening, it was found that f3-aminoalkyl boronic esters (from 1,2-cyclic sulfamidates) can be homologated in a 50% yield, while y-aminoalkyl boronic esters are completely unreactive to a range of homologation conditions.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:680108 |
| Date | January 2014 |
| Creators | Ursinyova, Nina |
| Publisher | University of Bristol |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
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