Synthesis and Comparison of the Reactivity of Allyl Fluorides and ...

Figure 4.3 Structure of co-product (144)
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Chapter Four
Starting Substrate Product Yield (%)*
(125) (145)
(126)
Table 4.2 Yields obtained of (145) and (146)
* Yield based on conversion in 1 H NMR spectrum
Therefore, as the Pd(II) intermediates could not be isolated pure, they were not reacted
further with triphenylphosphine in order to obtain the desired substituted products (Scheme
4.5). Similarly, pure products could not be isolated using the method described by
Bäckvall. [30] Subsequently, an alternative method by Hayashi et al. [31] was employed, where
(126) was stirred in THF, followed by the addition of 4 equivalents of triphenylphosphine
and sodium dimethylmalonate (Scheme 4.6). The reaction mixture was stirred overnight.
After which the formed precipitate was filtered off and solvent removed in vacuo to give the
crude product which was purified by column chromatography [hexane: ethyl acetate
(70:30)], affording the novel desired product as a colourless oil in 44 % yield, which was
characterised by 1 H NMR spectroscopy and mass spectrometry.
Scheme 4.6 Synthesis of (147)
(146)
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