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

IV
Appendix
mixture was stirred at -78 ºC for 1h, the precipitate formed was isolated and analysis by 1 H
and 19 F NMR revealed no starting material to be present, however dominance by PPh3,
hindered full analysis of the spectrum.
Reaction of 2-(2-fluorobut-3-enyl)isoindoline-1,3-dione with Pd(dba)2 at r.t
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 (273 mg, 0.48 mmol) was added to the flask in
the dry box, and then reattached to the Schlenk line. Anhydrous toluene (10 cm 3 ) and 2-(2fluorobut-3-enyl)isoindoline-1,3-dione
(104 mg, 0.48 mmol) were added and the reaction
mixture was stirred at room temperature for 6h. After removal of the reaction solvent the
mixture analysed by 1 H and 19 F NMR spectroscopy confirming that no reaction had occurred
as only starting material was observed. The same reaction conditions had simultaneously
been applied to 2-fluorobut-3-enyl benzoate and unfortunately the same disappointing result
was obtained.
Reaction of 2-(2-fluorobut-3-enyl)isoindoline-1,3-dione with Pd(dba)2 at 30 – 70 ºC
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 (263 mg, 0.46 mmol) was added to the flask in
the dry box, and then reattached to the Schlenk line. Anhydrous toluene (10 cm 3 ) and 2-(2fluorobut-3-enyl)isoindoline-1,3-dione
(100 mg, 0.46 mmol) were added and the reaction
mixture was stirred at 30 ºC overnight. The following day no precipitate or colour change
was observed, therefore, the temperature was increased to 35 ºC, and stirred for a further 2
hours, however, no notable change was observed. Therefore, the temperature was increased
further to 40 ºC for 1 hour and then stirred at 50 ºC for 3 hours, before finally refluxing at 70
ºC for 24 hours. After which a yellow solution was observed with a dark precipitate. The
yellow solution was transferred via cannula and dried in vacuo. Both 1 H and 19 F NMR
spectroscopy showed that only starting material and dba were present. The dark precipitate
was also dried in vacuo and analysed by 1 H and 19 F NMR spectroscopy with some difficulty
as it was not fully soluble in CDCl3 or C6D6, therefore, deuterated toluene was used, however,
only dba and starting material were present.
Reaction of 2-fluorobut-3-enyl benzoate with Pd(dba)2 at 30 – 70 ºC
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 (296 mg, 0.52 mmol) was added to the flask in
the dry box, and then reattached to the Schlenk line. Anhydrous toluene (10 cm 3 ) and 22fluorobut-3-enyl
benzoate (100 mg, 0.52 mmol) were added and the reaction mixture was
stirred at 30 ºC overnight. The following day no precipitate or colour change was observed,