:
R. Zurawin´ski et al. / Tetrahedron: Asymmetry 12 (2001) 3139–3145
3143
4H), 1.01 (t, J=7.2, 6H). 13C NMR (C6D6): l 193.75
4.13. Diethyl 2-hydroxy-2-phenylethanephosphonate 3d
(d, J=7.8), 153.15 (d, J=2.1), 148.97, 136.97, 127.36,
122.05, 62.11, 62.00, 36.16 (d, J=127.8), 16.32, 16.20.
31P NMR (CDCl3): l 29.61. 1H NMR (CDCl3): l
7.43–7.23 (m, 5H), 5.19–5.03 (m, 1H), 4.24–3.98 (m,
4H), 3.88 (s, 1H), 2.27–2.14 (m, 2H), 1.35 (t, J=7.0,
3H), 1.29 (t, J=7.1, 3H). 13C NMR (CDCl3): l 143.60
(d, J=14.9), 128.28, 127.47, 125.43, 68.60 (d, J=4.3),
61.83 (d, J=7.3), 61.68 (d, J=7.4), 35.80 (d, J=136.4),
16.25 (d, J=2.7), 16.13 (d, J=2.9). HRMS (CI): m/z
258.1020 (C12H19O4P requires 258.1021).
4.8. Diethyl 2-oxo-3-(1-naphthyl)propanephosphonate 2g
Obtained from diethyl methanephosphonate and
methyl 1-naphthylacetate as a colorless liquid after
distillation (bp 115–120°C/0.01 mmHg) in 73% yield.
31P NMR (CDCl3): l 20.28. 1H NMR (CDCl3): l
8.02–7.72 (m, 3H), 7.56–7.35 (m, 4H), 4.35 (s, 2H), 4.15
(quintet, J=7.0, 4H), 3.09 (d, J=22.8, 2H), 1.33 (t,
J=7.0, 6H). 13C NMR (CDCl3): l 191.56 (d, J=6.1),
133.70, 132.08, 130.06, 128.57, 128.36, 128.11, 126.34,
125.74, 125.40, 123.79, 62.60, 62.47, 48.77, 40.66 (d,
J=127.28), 16.19, 16.07.
4.14. Diethyl 2-hydroxy-3-phenylpropanephosphonate 3e
31P NMR (CDCl3): l 30.80. 1H NMR (CDCl3): l
7.33–7.12 (m, 5H), 4.31–3.93 (m, 5H), 3.57 (br. s, 1H),
2.95–2.70 (m, 2H), 2.05–1.75 (m, 2H), 1.27 (t, J=7.1,
6H). 13C NMR (CDCl3): l 137.57, 129.28, 128.24,
126.32, 67.41 (d, J=4.9), 61.66 (d, J=6.2), 61.61 (d,
J=6.5), 44.26 (d, J=16.2), 32.53 (d, J=138.6), 16.22,
16.10.
4.9. Chemical reduction of 2; synthesis of racemic 2-
hydroxyalkanephosphonates 3–general procedure
A solution of 2 in methanol or ethanol (depending on
the substituent at phosphorus) was treated with an
equimolar amount of sodium brohydride at 0°C. The
unreacted NaBH4 was decomposed with acetone and
the crude product was purified by column chromatog-
raphy using hexane-acetone as eluent to afford the
4.15. Diethyl 2-hydroxy-2-(2%-pyridyl)ethanephosphonate
3f
1
31P NMR (C6D6): l 38.81. H NMR (C6D6): l 8.41 (d,
desired 2-hydroxyalkanephosphonate
yield.
3 in 90–95%
J=4.8, 1H), 7.75 (d, J=8.0, 1H), 7.32–7.17 (m, 1H),
6.75–6.62 (m, 1H), 6.21–6.04 (m, 1H), 5.66–5.47 (m,
1H), 4.03–3.75 (m, 4H), 2.90–2.69 (m, 1H), 2.43–2.13
(m, 1H), 1.02 (t, J=7.1, 3H), 1.00 (t, J=7.1, 3H). 13C
NMR (C6D6): l 164.06 (d, J=16.2), 148.67, 136.51,
122.00, 120.32, 69.64 (d, J=4.6), 61.83 (d, J=6.1),
61.45 (d, J=6.4), 34.68 (d, J=138.2), 16.40, 16.27. MS
(CI): m/z 260 (M++1, 100). Anal. calcd for
C11H18NO4P: C, 50.96; H, 7.00; N, 5.40; O, 24.69; P,
11.95. Found: C, 50.90; H, 7.21; P, 11.83%.
4.10. Diethyl 2-hydroxypropanephosphonate 3a
31P NMR (CDCl3): l 30.61. 1H NMR (CDCl3): l
4.25–4.01 (m, 4H), 3.51 (s, 1H), 2.03–1.82 (m, 2H), 1.32
(t, J=7.1, 6H), 1.26 (dd, J=6.2, J=2.4, 3H). 13C NMR
(CDCl3): l 62.61 (d, J=4.9), 61.62 (d, J=6.3), 61.55 (d,
J=6.5), 35.03 (d, J=137.4), 24.13 (d, J=15.9), 16.24,
16.13.
4.11. Dimethyl 2-hydroxyhexanephosphonate 3b
4.16. Diethyl 2-hydroxy-3-(1%-naphthyl)propane-
phosphonate 3g
31P NMR (CDCl3): l 33.90. 1H NMR (CDCl3): l
4.10–3.85 (m, 1H), 3.73 (d, J=10.8, 3H), 3.72 (d,
J=11.0, 3H), 3.38 (d, J=3.2, 1H), 2.16–1.74 (m, 2H),
1.60–1.15 (m, 6H), 0.86 (t, J=6.9, 3H). 13C NMR
(CDCl3): l 65.99 (d, J=5.1), 52.10 (d, J=6.7), 51.97 (d,
J=7.2), 37.73 (d, J=15.4), 32.37 (d, J=137.9), 27.25,
22.19, 13.65. MS (CI): m/z 211 (M++1, 100). Anal.
calcd for C8H19O4P: C, 45.71; H, 9.11; O, 30.44; P,
14.73. Found: C, 45.82; H, 9.10; P, 14.60%.
31P NMR (CDCl3): l 30.61. 1H NMR (CDCl3): l
8.11–8.04 (m, 1H), 7.90–7.73 (m, 2H), 7.58–7.12 (m,
4H), 4.52–4.31 (m, 1H), 4.15–3.92 (m, 4H), 3.47–3.20
(m, 3H), 2.00 (dd, J=17.2, J=6.0, 2H), 1.28 (t, J=7.6,
3H), 1.24 (t, J=7.5, 3H). 13C NMR (CDCl3): l 133.80,
132.02, 128.86, 128.61, 128.05, 127.62, 127.32, 125.90,
125.46, 125.42, 123.73, 66.86 (d, J=4.4), 61.75, 61.63,
41.44 (d, J=15.5), 33.01 (d, J=138.5), 16.23, 16.11.
HRMS (CI): m/z 323.1412 (C17H23O4P+H requires
323.1412)
4.12. Dimethyl 2-hydroxy-5-phenylpentanephosphonate
3c
31P NMR (CDCl3): l 33.54. 1H NMR (CDCl3): l
7.32–7.10 (m, 5H), 4.12–3.90 (m, 1H), 3.74 (d, J=11.0,
3H), 3.71 (d, J=10.8, 3H), 3.50–3.30 (br. s, 1H), 2.62
(t, J=7.0, 2H), 2.05–1.40 (m, 6H). 13C NMR (CDCl3):
l 141.83, 127.99, 127.86, 125.31, 65.71 (d, J=4.9),
52.01 (d, J=6.5), 51.84 (d, J=6.8), 37.47 (d, J=15.2),
35.24, 32.32 (d, J=137.8), 26.85. HRMS (CI): m/z
273.1253 (C13H21O4P+H requires 273.1256). Anal. calcd
for C13H21O4P: C, 57.35; H, 7.77; O, 23.50; P, 11.38.
Found: C, 57.30; H, 7.85; P, 11.45%.
4.17. Dimethyl 2-acetoxypropanephosphonate 4a
31P NMR (CDCl3): l 27.09. 1H NMR (CDCl3): l
5.25–5.03 (m, 1H), 4.07 (quintet, J=7.3, 4H), 2.32–1.84
(m, 2H), 2.00 (s, 3H), 1.33 (d, J=5.4, 3H), 1.29 (t,
J=7.2, 6H). 13C NMR (CDCl3): l 169.90, 66.00, 61.64,
61.54, 32.53 (d, J=140.1), 21.04, 20.88, 16.27, 16.14.
MS (CI): m/z 239 (M++1, 100). Anal. calcd for
C9H19O5P: C, 45.38; H, 8.04; O, 33.58; P, 13.00. Found:
C, 45.21; H, 8.16; P, 12.81%.