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

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Chapter Six
260.3 Hz, ArCF), 166.3 (C=O); δF -109.5 (1F, s, CF). m/z (EI + ) 266 ([M] + , 8 %). HRMS
(EI) 266.11345 (C14H19O2FSi requires 262.11336).
6.2.19 Preparation of (2-Fluoro-but-3-enyloxymethyl)-benzene (73) [8]
The title compound was prepared following the method
outlined by Gouverneur et al. [8] without modification.
A 100 cm 3 , three-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 (4-Benzyloxy-but-2-enyl)-
trimethylsilane (76 mg, 0.31 mmol), anhydrous MeCN (5 cm 3 ) and Selectfluor (115 mg,
0.31 mmol). The reaction mixture was stirred at room temperature under argon for 48 h.
After which purification by flash chromatography [diethyl ether: hexane (5:95)] afforded the
product as an oil (18 mg, 33 % yield). δH 3.49-3.52 (1H, m, Hd), 3.58 (1H, m, He), 4.53
(2H, AB, 2 JAB = 12.0 Hz, CHAHBAr), 5.03 (1H, dm, 2 JHF = 48.3 Hz, CHF), 5.23 (1H, ap.dt,
3 JHH = 10.8 Hz, 2 JHH = 4 JHH = 1.4 Hz, Hb), 5.35 (1H, ap.ddt, 3 JHH = 17.2 Hz, 4 JHF = 2.9 Hz,
2 JHH = 4 JHH = 1.4 Hz, Ha),), 5.83 (1H, dddd, 3 JHH = 17.2 Hz, 3 JHF = 15.2 Hz, 3 JHH =10.8 Hz,
3 JHH = 5.6 Hz, Hc), 7.20-7.38 (5H, m, ArH); δF -185.0 (1F, s, CHF).
6.2.20 Preparation of 2-(2-Fluoro-but-3-enyl)-isoindole-1,3-dione (74) [8]
The title compound was prepared following the method
outlined by Gouverneur et al. [8] without modification. A
100 cm 3 , three-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 2-(4-
trimethylsilanyl-but-2-enyl)-isindole-1,3-dione (0.85 g, 3.11 mmol), anhydrous MeCN (12
cm 3 ) and Selectfluor (1.10 g, 3.11 mmol). The reaction mixture was stirred at room
temperature under argon for 48 h. After which purification by flash chromatography
[diethyl ether: hexane (30: 70)] afforded the product as a white solid (0.68 g, 77 %). δH 3.76
(1H, ddd, 3 JHF = 26.2 Hz, 2 JHH = 14.5 Hz, 3 JHH = 4.1 Hz, Hd), 3.97 (1H, ddd, 3 JHF = 14.5 Hz,
2 JHH = 14.5 Hz, 3 JHH = 8.2 Hz, He), 5.02-5.25 (1H, dm, 2 JHF = 48.9 Hz, CHF) 5.28 (1H,
ap.dt, 3 JHH = 11.0 Hz, 2 JHH = 4 JHH = 1.2 Hz, Hb), 5.39 (1H, ap.ddt, 3 JHH = 17.2 Hz, 4 JHF = 3.1
Hz, 2 JHH = 4 JHH = 1.2 Hz, Ha), 5.87 (1H, dddd, 3 JHH = 17.2 Hz, 3 JHF = 14.8 Hz, 3 JHH = 11.0