Anthony KERMAGORET - THESES ET MEMOIRES DE L'UDS

Chapitre VI
Ph), 131.9 - 132.1 (overlapping s and d, p-C and o-C of P-Ph), 141.2 (d, 3 JPC = 11.3 Hz, ipso-
C of OC-Ph), 185.2 (s, CO); 31 P{ 1 H} NMR (CDCl3, 121.5 MHz): δ 17.0.
Synthesis of (benzoylmethylene)phenyldimethylphosphorane 11
3.200 g (16.10 mmol) of α-bromoacetophenone were added to a solution of 2.200 g
(16.10 mmol) of phenyldimethylphosphine in 20 mL of toluene and stirred for 24 h at room
temperature. The solvent was removed was filtered with a canula and the phosphonium salt
washed with toluene (20 mL) and dried under vacuum. 1 H NMR (300 MHz, MeOD): δ 2.38
(6H, d, 2 JPH = 14.7 Hz, CH3), 3.31 (2H, quint, J = 1.5 Hz, CH2), 7.52-7.57 (2H, m, aromatic
H), 7.67-7.72 (3H, m, aromatic H), 7.75-7.81 (1H, m, aromatic H), 7.96-8.05 (4H, m,
aromatic H); 31 P{ 1 H} NMR (MeOD, 121.5 MHz): δ 23.3.
NaH was added to a suspension of the phosphonium salt in toluene and the mixture
was stirred overnight at room temperature. The solution was transferred with a canula to
eliminate NaBr and unreacted NaH. The solvent was removed under reduced pressure and a
pale yellow powder was obtained which dried under vacuum overnight. Yield: 3.800 g, 92%.
1 H NMR (300 MHz, CDCl3): δ 2.03 (6H, t, 2 JPH = 13.5 Hz, CH3), 4.23 (1H, d, 2 JPH = 25.8 Hz,
P-CH), 7.35 (3H, m, aromatic H), 7.52 (3H, m, aromatic H), 7.77 (2H, m, aromatic H) and
7.91 (2H, m, aromatic H); 13 C{ 1 H} NMR (CDCl3, 75.5 MHz): δ 12.4 (d, 1 JPC = 62.1 Hz,
CH3), 51.0 (d, 1 JPC = 111.7 Hz, P-CH), 126.6 (s, CH of OC-Ph), 127.8 (s, CH of OC-Ph),
128.9 (d, 1 JPC = 87.0 Hz, ipso-C of P-Ph), 129.2 (d, 2 JPC = 11.9 Hz, o-C of P-Ph), 129.5 (s, p-
C of OC-Ph), 130.4 (d, 3 JPC = 10.2 Hz, m-C of P-Ph), 132.0 (d, 4 JPC = 2.7 Hz, p-C of P-Ph),
140.8 (d, 3 JPC = 13.4 Hz, ipso-C of OC-Ph), 185.2 (d, 2 JPC = 2.9 Hz, CO); 31 P{ 1 H} NMR
(CDCl3, 121.5 MHz): δ 7.4.
Synthesis of ortho-(methoxy)phenylcarbonylmethylene(triphenylphosphorane) 12 56
Synthesis of 2-bromo-1-(2-methoxyphenyl)ethanone 66
To solution of 15.000 g (100.00 mol) of 1-(2-methoxyphenyl)ethanone in 200 mL of
CCl4 at reflux, was added a solution of Br2 (5.5 mL, 100.00 mol) over a period of 50 min.
After reaction, the solvents were removed under reduced pressure and the solid residue was
dissolved in 100 mL of a mixture of diethylether/pentane (1/1). The solution was cooled at 0
°C to precipitate 2-bromo-1-(2-methoxyphenyl)ethanone which was filtered and dried. The
pale green solid product proved to be sensitive and was used immediately (yield: 60%).
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