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

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Chapter Six
4 JHH = 1.2 Hz, ArH-3), 7.14 (1H, td, 3 JHH = 78 Hz, 4 JHH = 1.2 Hz, ArH-5), 7.46 (1H, dddd,
3 JHH = 8.6 Hz, 3 JHH = 7.4 Hz, 4 JHF = 5.1 Hz, 4 JHH = 2.0 Hz, ArH-4), 7.90 (1H, td, 3 JHH = 7.4
Hz, 4 JHH = 2.0 Hz, ArH-6); δC 61.4 (CHCH2), 63.9 (OCH2), 75.5 (OCH2CH), 110.7
(CHCH2), 117.0 (d, 2 JCF = 22.1 Hz, ArCH-3), 118.2 (d, 2 JCF = 9.1 Hz, ArC-1), 124.1 (d, 4 JCF
= 3.0 Hz, ArCH-5), 132.3 (ArCH-6), 134.8 (d, 3 JCF = 9.1 Hz, ArCH-4), 162.0 (d, 1 JCF =
260.6 Hz, ArCF), 163.2 (d, 3 JCF = 3.0 Hz, C=O); δF -108.84 (1F, s, CF). m/z (FAB + ) 635
([M-Cl] + , 100 %), 670 ([M] + , 22 %).
6.3.8 Preparation of ((butenyl-(1,2,3-�)-isoindoline-1,3-dione)bis(triphenylphosphine)
palladium fluoride (132)
The novel compound was prepared following the
method outlined by Gouverneur et al. [14] A 50 cm 3 ,
two-necked round-bottom flask was equipped with a
magnetic stirring bar and Rotaflo tap and attached to
a Schlenk line. After flame-drying under high
vacuum, the flask was cooled and filled with nitrogen. Pd(dba)2 (0.05 g, 0.09 mmol), PPh3
(0.24 g, 0.91 mmol) and anhydrous CDCl3 were added to the reaction flask in a dry box.
Subsequently, the flask was reattached to the Schlenk line, filled with nitrogen and charged
with 2-(2-fluorobut-3-enyl)isoindoline-1,3-dione (0.10 g, 0.46 mmol), after stirring the
reaction for 1 minute a small aliquot was transferred into an NMR tube. The progress of the
reaction was monitored by 1 H and 19 F{ 1 H} NMR (see Table 6.1 and Table 6.2) and after 1 h
electrospray mass spectrometry indicated the formation of the allylpalladium cationic
complex, (ES + ) 830 (M + , 23 %) 568 (M + -PPh3, 100 %). However, starting material had not
been fully consumed, hence, the reaction mixture was stirred overnight, solvent then
removed in vacuo, and reaction mixture purified by column chromatography [DCM: hexane
(70:30)]. No desired product was isolated but an elimination product; 2-(buta-1,3-
dienyl)isoindoline-1,3-dione (133), had also formed and was isolated as a yellow solid (45
mg, 50 %).