Anthony KERMAGORET - THESES ET MEMOIRES DE L'UDS

Chapitre VI
and the solution was stirred for 3 h from -78 °C to room temperature. The white precipitate of
LiCl was eliminated by filtration with a canula and the pentane was removed under reduced
pressure. The white oil obtained was distilled under reduced pressure (110 °C, 0.8 mbar). The
phosphine was isolated as a colorless liquid. Yield: 1.560 g, 40%. 1 H NMR (300 MHz,
CDCl3): δ 1.20 (18H, d, 3 JPH = 11.7 Hz, CH3), 7.34 – 7.38 (3H, m, aromatic H) and 7.64 –
7.72 (2H, m, aromatic H); 31 P{ 1 H} NMR (CDCl3, 121.5 MHz): δ 40.5 (s)
Synthesis of phenyldi(n-butyl)phosphine 55
4.34 mL (32.00 mmol) of PPhCl2 were dissolved in 60 mL of pentane and cooled to -
78 °C. 40 mL of a n-BuLi solution in pentane (1.6 mol·L -1 , 64.00 mmol) were slowly added
and the solution was stirred for 3 h from -78 °C to room temperature. The white precipitate of
LiCl was eliminated by filtration with a canula and the pentane was removed under reduced
pressure. The white oil obtained was distilled under reduced pressure (120 °C, 0.8 mbar). The
phosphine was isolated as a colorless liquid. Yield: 5.180 g, 73%. 1 H NMR (300 MHz,
CD2Cl2): δ 0.91 (6H, t, 3 JHH = 6.9 Hz, CH3), 1.41 (8H, m, CH2-CH2), 1.79 (4H, br m, P-CH2),
7.40 (3H, m, aromatic H) and 7.55 (2H, m, aromatic H); 31 P{ 1 H} NMR (CD2Cl2, 121.5 MHz):
δ -20.0 (br s).
Synthesis of (benzoylmethylene)tri(n-butyl)phosphorane 6
3.700 g (18.60 mmol) of α-bromoacetophenone were added to a solution of 3.760 g
(18.60 mmol) of tri(n-butyl)phosphine in 30 mL of toluene and stirred for 24 h at room
temperature. The phosphonium salt was then filtered with a canula, washed with toluene (40
mL) and dried under vacuum (the phosphonium salt has not been characterized by 31 P{ 1 H}
NMR or 1 H NMR). The dried salt was dissolved in a mixture of 60 mL of distilled water and
60 mL of MeOH and, an aqueous solution of NaOH (2.0 M) was added to the solution until
pH 8 was reached. The solution became cloudy and the phosphorane 6 settled overnight as a
red oil and the solution was eliminated with a canula. 6 was washed with water and dried
under vacuum overnight. Yield: 5.400 g, 91%. 1 H NMR (300 MHz, CDCl3): δ 0.92 (9H, t,
3 JHH = 7.2 Hz, CH3), 1.45 (12H, m, CH2-CH2), 2.04 (6H, m, P-CH2), 3.72 (1H, d, 2 JPH = 22.8
Hz), 7.31 (3H, m, aromatic H), 7.85 (2H, m, aromatic H); 13 C{ 1 H} NMR (CDCl3, 75.5 MHz):
δ 13.7 (s, CH3), 21.5 (d, 1 JPC = 55.1 Hz, P-CH2), 24.1 (d, 2 JPC = 15.0 Hz, P-CH2-CH2), 24.3
(d, 3 JPC = 3.9 Hz, CH2-CH3), 47.8 (d, 1 JPC = 104.3 Hz, P-CH), 126.5 (s, aromatic CH), 127.7
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