My PhD dissertation - Institut Fresnel

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hexanes (15 mL) and the reaction mixture was heated to reflux for 12 h. At 25 °C, the
precipitate was filtered under inert atmosphere and recrystallized from ethyl acetate to afford
white needles; m.p. 173 - 175 °C; yield: 4.40 g (98%).
1 H NMR: δ = 2.55 (d, J = 13.4 Hz, 2 H), 2.5 (m, 6 H), 1.6 (m, 12 H), 1.23 (s,
9 H), 0.99 (t, J = 7.0 Hz, 9 H) ppm.
13 C NMR: δ = 33.3 (d, J = 42 Hz), 32.3 (d, J = 5 Hz), 31.8 (d, J = 7 Hz), 24.1 (d, J
= 5 Hz), 24.0 (d, J = 15 Hz), 21.2 (d, J = 46 Hz), 13.5 ppm.
31 P NMR: δ = 34.9 ppm.
Butyltriethylphosphonium iodide (28e) [167] : Analogously prepared from triethylphosphine
(3.1 g, 26 mmol) and butyl iodide (4.3 mL, 7.0 g, 39 mmol); white needles (from ethyl
acetate); m.p. 194 - 196 °C; yield: 7.44 g (96%).
1 H NMR: δ = 2.53 (dq, J = 13.0, 7.7 Hz, 6 H), 1.6 (m, 6 H), 1.33 (dt, J = 18.0,
7.7 Hz, 9 H), 0.99 (t, J = 7.2 Hz, 3 H) ppm.
13 C NMR: δ = 24.0 (d, J = 15 Hz), 23.7 (d, J = 5 Hz), 18.2 (d, J = 47 Hz), 13.5,
12.7 (d, J = 49 Hz), 6.3 (d, J = 6 Hz) ppm.
31 P NMR: δ = 41.1 ppm.
3.4 Alkaline Decomposition of Phosphonium Salts
General procedure: The phosphonium salt (1.0 mmol) was suspended in butanol (5 .0 mL) and a 6.0
M aqueous potassium hydroxide solution (1.0 mL) was added. Tributylphosphine oxide or
triisopropylphosphine oxide (1 mmol), depending on the expected reaction products, was immediately
added as internal standard. The reaction mixture was then heated at 110 °C until no trace of starting
phosphonium remained. The gases formed during the decomposition were bubbled into a solution of
bromine (0.2 mL, 0.5 g, 3 mmol) in chloroform (5 mL). After the gas evolution ceased, cyclohexane
(20 mL) was added and the solvents were removed under reduced pressure. The residue was dissolved
in diethyl ether (15 mL), dried with sodium sulfate and evaporated to dryness. 31 P NMR experiment
was directly run on the crude mixture without any further purification.