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

Scheme 4.4 Attempted fluorination of 1,3-diphenylallyl ethyl carbonate
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Chapter Four
However, the limited scope of this previous report did not, necessarily, indicate that such a
transformation was not achievable.
Prior to the fluoride ion reaction chemistry, some of the Pd-allyl species prepared in Chapter
Three were reacted with conventional carbon based nucleophiles to demonstrate that they
followed established reaction trends.
4.2.1 Reactions of palladium chloro-bridged complexes with nucleophiles
Initially the palladium (II) chloro-bridged dimers (125) and (126) were reacted with sodium
acetylacetonate, following the protocol outlined by Hayashi and co-workers. [29] The Pd
dimer was stirred in THF and cooled to 0 ºC, followed by addition of sodium acetyl
acetonate to the reaction flask and the mixture was then stirred at 0 ºC for 1 hour. After
which, the reaction mixture was quenched with water, extracted with diethyl ether, the
organic layer dried over magnesium sulphate and the solvent removed in vacuo to afford the
products (145) and (146) in 66 % yield (Scheme 4.6) (Table 4.2).
Scheme 4.5 Synthesis of (145) and (146)
However, the reactions did not go to completion as the co-product palladium
acetylacetonate (144) was also formed which was identified by single crystal X-ray
crystallography (Figure 4.3). Although attempts were made by column chromatography and
recrystallisation, it was difficult to separate the desired product fully from (144).