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

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Chapter Six
drying under high vacuum, the flask was cooled and filled with nitrogen. The funnel was
charged with 4-(trifluoromethyl)benzoyl chloride (3.06 g, 2.17 cm 3 , 14.69 mmol) and
pyridine (1.3 cm 3 ). The reaction flask was charged with (±)3-butene-1,2-diol (1.05 g, 1 cm 3 ,
11.88 mmol) and pyridine (5 cm 3 ). The reaction flask was cooled to -35 ºC (isopropanol:
dry ice mixture). The 4-(trifluoromethyl)benzoyl chloride solution was then dropped into
the cooled reaction flask, and the reaction mixture was stirred for 17 h. After which the
reaction mixture was poured into water and extracted with DCM. The extracts were then
washed with 2M HCl and NaHCO3 solution, after which it was dried over Na2SO4, and
concentrated in vacuo. Purification by chromatography [chloroform: hexane (80:20)]
afforded the product as a white solid (2.03 g, 66 %). δH 2.34-2.41 (1H, bs, OH), 4.25 (1H,
dd, 2 JHH = 11.3 Hz, 3 JHH = 7.0 Hz, Hd), 4.35 (1H, dd, 2 JHH = 11.3 Hz, 3 JHH = 3.5 Hz, He),
4.44-4.49 (1H, m, CHOH), 5.20 (1H, ap.dt, 3 JHH = 10.6 Hz, 2 JHH = 4 JHH = 1.6 Hz, Hb), 5.36
(1H, ap.dt, 3 JHH = 17.2 Hz, 2 JHH = 4 JHH = 1.6 Hz, Ha), 5.86 (1H, ddd, 3 JHH = 17.2 Hz, 3 JHH =
10.6 Hz, 3 JHH = 5.9 Hz, Hc), 7.61 (2H, tm, 3 JHH = 8.2 Hz, ArH-3), 8.07 (2H, dm, 3 JHH = 8.2
Hz, ArH-2); δC 68.6 (OCH2), 71.0 (CHOH), 117.4 (CHCH2), 123.6 (q, 1 JCF = 272.9 Hz,
ArCF3), 125.5 (ArCH-3), 130.1 (ArCH-2), 133.0 (ArC-1), 134.7 (q, 2 JCF = 32.7 Hz, ArC-4),
136.1 (CHCH2), 165.5 (C=O); δF – 63.1 (3F, s, CF3). m/z (FAB + ) 261 ([MH] + , 32 %) 123
([M-OCH2CHOHCH= CH2] + , 100 %). HRMS (FAB) 261.07357 (C12H12O3F3 requires
261.07355).
6.2.34 Preparation of ((2-chlorobut-3-enyloxy)methyl)benzene (106)
The novel compound was prepared following the
method outlined by Munyemana et al. [11] 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 reaction flask was then charged with 1-(benzyloxy)but-3-en-2-ol (0.37 g, 2.07
mmol) and anhydrous DCM (7 cm 3 ). The flask was then cooled to 0 ºC using an ice bath.
Once cooled tetramethyl-�-chloroenamine was added (0.28 g, 0.28 cm 3 , 2.07 mmol) via
syringe. The reaction mixture was then stirred at room temperature for 3 h. After which
purification by chromatography [DCM/cyclohexane (50/50)] afforded the product as an oil
(0.21 g, 52 %). Elemental analysis: Found: C, 67.07; H, 6.55. Calc. for C11H13OCl: C,
67.18; H, 6.66 %. δH 3.58 (1H, dd, 2 JHH = 11.3 Hz, 3 JHH = 6.3 Hz, Hd), 3.61 (1H, dd, 2 JHH =
11.3 Hz, 3 JHH = 6.7 Hz, He), 4.41-4.46 (1H, m, CHCl), 4.53 (2H, AB, 2 JAB = 12.1 Hz,
CHAHBAr), 5.18 (1H, ap.dt, 3 JHH = 10.2 Hz, 2 JHH = 4 JHH = 0.8 Hz, Hb), 5.32 (1H, ap.dt, 3 JHH