PAPER
Synthesis of Aryl-H-phosphinates
2493
Colorless oil; yield: 8.7 g (50%); bp 80 °C (0.1 mmHg).
31P NMR (161.97 MHz, DMSO-d6): d = 21.84 (s).
1H NMR (400.13 MHz, DMSO-d6): d = 7.54–7.47 (m, 1 H), 7.54 (d,
HRMS (Q-TOF MS ES+): m/z [M + H]+ calcd for C9H11F3O2P:
239.0449; found: 239.0446.
3
3
1JHP = 567.9 Hz, 1 H), 7.31 (ddt, JHP = 13.4 Hz, JHH = 7.3 Hz,
3
4
4JHH = 1.3 Hz, 1 H), 7.26 (ddd, JHP = 15.7 Hz, JHH = 2.6 Hz,
3
4
4JHH = 1.3 Hz, 1 H), 7.23 (ddd, JHH = 8.4 Hz, JHH = 2.6 Hz,
4JHH = 1.3 Hz, 1 H), 4.14–3.98 (m, 2 H), 3.82 (s, 3 H), 1.27 (t,
3JHH = 7.1 Hz, 3 H).
Ethyl [1,1¢-Biphenyl]-4-ylphosphinate (Table 2, Entry 10)1
The general procedure described above was applied starting from 4-
bromo-1,1¢-biphenyl (35.0 g), but after hydrolysis, the title product
was purified via a modified process. The oily residue was dissolved
in Et2O (300 mL) and washed with aq NaHCO3 soln (4 × 30 mL,
10%) and H2O (30 mL). The organic layer was dried over Na2SO4,
filtered and evaporated. The resulting solid was triturated with n-
pentane (3 × 30 mL) and n-heptane (2 × 30 mL) at 50 °C, and then
dried under vacuum.
13C NMR (100.62 MHz, DMSO-d6): d = 159.73 (d, 3JCP = 16.8 Hz),
3
132.26 (d, 1JCP = 128.8 Hz), 130.80 (d, JCP = 16.1 Hz), 122.89 (d,
4
2
2JCP = 11.7 Hz), 119.40 (d, JCP = 2.9 Hz), 115.57 (d, JCP = 13.2
Hz), 62.30 (d, 2JCP = 5.9 Hz), 55.81 (s), 16.64 (d, 3JCP = 5.9 Hz).
31P NMR (161.97 MHz, DMSO-d6): d = 24.54 (s).
HRMS (Q-TOF MS ES+): m/z [M + H]+ calcd for C9H14O3P:
White solid; yield: 12.2 g (49%); mp 36–38 °C.
201.0681; found: 201.0683.
1H NMR (400.13 MHz, DMSO-d6): d = 7.92–7.78 (m, 4 H), 7.78–
7.70 (m, 2 H), 7.61 (d, 1JPH = 567.1 Hz, 1 H), 7.56–7.48 (m, 2 H),
7.47–7.44 (m, 1 H), 4.18–4.02 (m, 2 H), 1.30 (t, 3JHH = 7.1 Hz, 3 H).
Ethyl (4-Fluorophenyl)phosphinate (Table 2, Entry 7)1,13
The product was prepared starting from 4-fluorobromobenzene
(30.6 g) and was purified by distillation.
13C NMR (100.62 MHz, DMSO-d6): d = 144.50 (d, 4JCP = 2.9 Hz),
5
2
138.88 (d, JCP = 1.5 Hz), 131.20 (d, JCP = 12.4 Hz), 130.31 (d,
1JCP = 117.1 Hz), 129.09 (s), 128.41 (s), 127.14 (s), 127.07 (d,
3JCP = 13.9 Hz), 62.36 (d, 2JCP = 6.6 Hz), 16.73 (d, 3JCP = 5.9 Hz).
Colorless oil; yield: 9.7 g (53%); bp 72 °C (0.15 mmHg).
1H NMR (400.13 MHz, DMSO-d6): d = 7.88–7.76 (m, 2 H), 7.58 (d,
1JHP = 571.9 Hz, 1 H), 7.48–7.40 (m, 2 H), 4.18–3.98 (m, 2 H), 1.28
(t, 3JHH = 7.1 Hz, 3 H).
31P NMR (161.97 MHz, DMSO-d6): d = 24.40 (s).
HRMS (Q-TOF MS ES+): m/z [M + H]+ calcd for C14H16O2P:
13C NMR (100.62 MHz, DMSO-d6): d = 164.90 (dd, 4JCP = 2.9 Hz,
247.0888; found: 247.0888.
1JCF = 251.0 Hz), 133.59 (dd, 2JCP = 9.5 Hz, 3JCF = 13.9 Hz), 126.78
1
4
2
(dd, JCP = 132.1 Hz, JCF = 2.9 Hz), 116.17 (dd, JCF = 21.2 Hz,
3JCP = 14.6 Hz), 61.92 (d, 2JCP = 5.9 Hz), 16.17 (d, 3JCP = 6.6 Hz).
Ethyl (4-Phenoxyphenyl)phosphinate (Table 2, Entry 11)
The general procedure described above was applied starting from 1-
bromo-4-phenoxybenzene (37.4 g). Purification was achieved by
treatment of the residue with n-pentane (6 × 30 mL) at reflux tem-
perature. The solid obtained was dried under vacuum.
31P NMR (161.97 MHz, DMSO-d6): d = 23.24 (s).
HRMS (Q-TOF MS ES+): m/z [M + H]+ calcd for C8H11FO2P:
189.0481; found: 189.0476.
White solid; yield: 13.4 g (51%); mp 31–33 °C.
Ethyl (3-Fluorophenyl)phosphinate (Table 2, Entry 8)1
The product was prepared starting from 3-fluorobromobenzene
(30.6 g) and was purified by distillation
1H NMR (400.13 MHz, DMSO-d6): d = 7.80–7.68 (m, 2 H), 7.54 (d,
1JPH = 566.1 Hz, 1 H), 7.52–7.40 (m, 2 H), 7.30–7.22 (m, 1 H),
7.18–7.08 (m, 4 H), 4.15–4.08 (m, 2 H), 1.28 (t, 3JHH = 7.1 Hz, 3 H).
13C NMR (100.62 MHz, DMSO-d6): d = 166.34 (d, 4JCP = 2.9 Hz),
160.12 (s), 138.26 (d, 2JCP = 13.2 Hz), 135.59 (s), 130.04 (s), 128.70
(d, one transition is missing), 125.25 (s), 122.86 (d, 3JCP = 14.6 Hz),
66.95 (d, 2JCP = 5.9 Hz), 21.45 (d, 3JCP = 6.6 Hz).
Colorless oil; yield: 10.6 g (56%); bp 64 °C (0.1 mmHg).
1H NMR (400.13 MHz, DMSO-d6): d = 7.70–7.50 (m, 4 H), 7.59 (d,
1JHP = 577.8 Hz, 1 H), 4.18–4.00 (m, 2 H), 1.28 (t, 3JHH = 7.1 Hz, 3
H).
1
13C NMR (100.62 MHz, DMSO-d6): d = 161.90 (dd, JCF = 247.4
31P NMR (161.97 MHz, DMSO-d6): d = 23.90 (s).
HRMS (Q-TOF MS ES+): m/z [M + H]+ calcd for C14H16O3P:
3
1
3
Hz, JCP = 19.0 Hz), 133.07 (dd, JCP = 128.1 Hz, JCF = 5.8 Hz),
131.49 (dd, 3JCF = 15.4 Hz, 3JCP = 7.3 Hz), 126.72 (dd, 2JCP = 11.7
263.0837; found: 263.0823.
4
4
2
Hz, JCF = 3.7 Hz), 120.16 (dd, JCP = 2.9 Hz, JCF = 21.2 Hz),
2
2
2
117.08 (dd, JCF = 22.0 Hz, JCP = 13.2 Hz), 62.16 (d, JCP = 6.6
Hz), 16.16 (d, 3JCP = 6.6 Hz).
Acknowledgment
31P NMR (161.97 MHz, DMSO-d6): d = 22.68 (d, 4JPF = 7.9 Hz).
HRMS (Q-TOF MS ES+): m/z [M + H]+ calcd for C8H11FO2P:
Sylvain Bianchi, Eric Gayon and Zofia Dziuganowska are grateful-
ly acknowledged for their practical work.
189.0481; found: 189.0477.
Ethyl [3-(Trifluoromethyl)phenyl]phosphinate (Table 2, Entry
9)
The product was prepared starting from 3-(trifluoromethyl)bro-
References
(1) (a) Pirat, J.-L.; Virieux, D.; Clarion, L.; Volle, J.-N.;
Bakalara, N.; Mersel, M.; Montbrun, J.; Cristau, H.-J. PCT
WO 2009004096, 2009; Chem. Abstr. 2009, 150, 98586.
(b) Volle, J.-N.; Filippini, D.; Krawczyk, B.; Kaloyanov, N.;
Van der Lee, A.; Maurice, T.; Pirat, J.-L.; Virieux, D. Org.
Biomol. Chem. 2010, 8, 1438.
(2) (a) van der Knapp, Th. A.; Klebach, T. h. C.; Lourens, R.;
Vos, M.; Bickelhaupt, F. J. Am. Chem. Soc. 1983, 105,
4026. (b) Yoshifuji, M.; Hirano, M.; Toyota, K. Tetrahedron
Lett. 1993, 34, 1043. (c) Wang, F.; Schwabacher, A.
Tetrahedron Lett. 1999, 40, 7641.
mobenzene (39.4 g) and was purified by distillation.
Colorless oil; yield: 9.4 g (39%); bp 69 °C (0.1 mmHg).
1H NMR (400.13 MHz, DMSO-d6): d = 8.15–8.00 (m, 3 H), 7.90–
7.80 (m, 1 H), 7.67 (d, 1JHP = 582.8 Hz, 1 H), 4.22–3.98 (m, 2 H),
1.29 (t, 3JHH = 7.1 Hz, 3 H).
13C NMR (100.62 MHz, DMSO-d6): d = 134.70 (d, 2JCP = 11.7 Hz),
1
3
132.03 (d, JCP = 128.1 Hz), 130.17 (d, JCP = 13.2 Hz), 129.62
(pent, 3JCF and 4JPC = 3.3 Hz), 127.11 (dq, 3JCF = 3.7 Hz, 2JCP = 13.2
Hz), 122.99 (q, 1JCF = 272.3 Hz), 62.37 (d, 2JCP = 6.6 Hz), 16.14 (d,
3JCP = 6.6 Hz).
(3) Yoshifuji, M.; Nakazawa, M.; Sato, T.; Toyota, K.
Tetrahedron 2000, 56, 43.
Synthesis 2011, No. 15, 2490–2494 © Thieme Stuttgart · New York