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

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Chapter Six
Hz, Ha), 5.19 (1H, d, 3 JHH = 17.2 Hz, Hb), 5.81 (1H, ddd, 3 JHH = 17.2 Hz, 3 JHH = 10.6 Hz,
3 JHH = 8.6 Hz, Hc), 7.05 (2H, tm, 3 JHH = 9.0 Hz, ArH-3), 7.96 (2H, dm, 3 JHH = 9.0 Hz, ArH-
2); δF -105.3 (1F, s, CF).
6.4.6 Preparation of dimethyl 2-(1-(4-(trifluoromethyl)benzoyloxy)but-3-en-2-yl)
malonate (149)
The novel compound was prepared following the
method outlined by Hayashi et al. [17] 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. The flask was charged with bis[�-chloro) bis(butenyl-(1,2,3-�)-4-
(trifluoromethyl)benzoate]dipalladium (100 mg, 0.13 mmol) and anhydrous THF (5 cm 3 ).
The reaction mixture was stirred at room temperature for 15 minutes, after which PPh3 (136
mg, 0.52 mmol) and sodium dimethylmalonate (81 mg, 0.52 mmol) were added and the
mixture stirred overnight. 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 product as a colourless oil (5 mg, 21 %). δH 3.27 (1H,
m, Hd), 3.58 (1H, d, 3 JHH = 8.6 Hz, CH(COOMe)2), 3.65 (6H, s, CH3), 4.36 (1H, dd, 2 JHH =
11.0 Hz, 3 JHH = 5.9 Hz, He), 4.43 (1H, dd, 2 JHH = 11.3 Hz, 3 JHH = 6.3 Hz, Hf), 5.15 (1H, d,
3 JHH = 11.0 Hz, Ha), 5.20 (1H, dt, 3 JHH = 17.2 Hz, Hb), 5.81 (1H, ddd, 3 JHH = 17.2 Hz, 3 JHH
= 10.2 Hz, 3 JHH = 8.6 Hz, Hc), 7.65 (2H, dm, 3 JHH = 8.2 Hz, ArH-3), 8.06 (2H, dm, 3 JHH =
8.2 Hz, ArH-2); δF -63.1 (3F, s, CF3).
6.4.7 Preparation of 1-fluoro-bis(phenylsulfonyl)methane (140) [18]
The title compound was prepared using a method outlined
by Shibata et al. without modification. [18] A 100 cm 3 , three-
necked round-bottomed flask was equipped with a magnetic
stirring bar, pressure equalising dropping funnel and Rotaflo
tap and attached to a Schlenk line. After flame-drying under high vacuum, the flask was
cooled and filled with nitrogen. The flask was charged with NaH (60 % oil dispersion, 135
mg, 3.38 mmol) and anhydrous THF (15 cm 3 ). The mixture was cooled to 0 °C using an ice
bath and bis(phenylsulfonyl)methane (1.00 g, 3.38 mmol) added. The reaction mixture was
then stirred at room temperature for 30 min. Selectfluor (1.20 g, 3.38 mmol) and anhydrous