PAPER
Facile Fluorination
3129
19F NMR (282 MHz, CDCl3): δ = –195.99 (d, J = 49 Hz).
13C NMR (75 MHz, CDCl3): δ = 6.7 (d, J = 2.5 Hz), 32.2, 98.1 (d,
J = 197.8 Hz), 202.3 (d, J = 24.3 Hz).
19F NMR (282 MHz, CDCl3): δ = –196.55 (d, J = 50 Hz).
Ethyl 2-Fluoro-3-oxohexanoate (2e)20
Colorless oil; yield: 164 mg (93%, Table 2, entry 8).
IR (KBr): 1760 (C=O), 1732 cm–1 (C=O).
N,N-Diethyl-2-fluoro-3-oxobutanamide (2k)22
Yellow oil; yield: 163 mg (93%, Table 2, entry 19).
1H NMR (300 MHz, CDCl3): δ = 0.86 (t, J = 7.3 Hz, 3 H, Me), 1.25
(t, J = 7.2 Hz, 3 H, Me), 1.58 (sext, J = 7.2 Hz, 2 H, CH2), 2.55–2.62
(m, 2 H, CH2), 4.23 (q, J = 7.2 Hz, 2 H, CH2), 5.16 (d, J = 49 Hz, 1
H, CHF).
1H NMR (300 MHz, CDCl3): δ = 1.05 (t, J = 7.2 Hz, 3 H, Me), 1.11
(t, J = 7.2 Hz, 3 H, Me), 2.24 (d, J = 5.2 Hz, 3 H, Me), 3.22–3.39
(m, 4 H, CH2), 5.33 (d, J = 50 Hz, 1 H, CHF).
13C NMR (75 MHz, CDCl3): δ = 13.3, 13.8, 16.1, 40.2, 62.5, 91.3
(d, J = 196.0 Hz), 164.1 (d, J = 24.1 Hz), 201.1 (d, J = 22.2 Hz).
19F NMR (282 MHz, CDCl3): δ = –195.95 (d, J = 49 Hz).
13C NMR (75 MHz, CDCl3): δ = 10.0, 11.7, 23.5, 38.3, 39.3 (d,
J = 3.7 Hz), 89.2 (d, J = 194.1 Hz), 160.6 (d, J = 19.7 Hz), 199.6 (d,
J = 24.8 Hz).
19F NMR (282 MHz, CDCl3): δ = –189.29 (d, J = 50 Hz).
Ethyl 2-Fluoro-3-oxo-4-phenylbutanoate (2f)
Colorless oil; yield: 224 mg (100%, Table 2, entry 9).
N,N-Dimethyl-2-fluoro-3-oxobutanamide (2l)20
Yellow oil; yield: 134 mg (91%, Table 2, entry 22).
1H NMR (300 MHz, CDCl3): δ = 1.26 (t, J = 7.2 Hz, 3 H, Me), 4.02
(d, J = 3.0 Hz, 2 H, CH2), 4.26 (q, J = 7.2 Hz, 2 H, CH2), 5.33 (d,
J = 48.9 Hz, 1 H, CHF), 7.25–7.38 (m, 5 H, HAr).
13C NMR (75 MHz, CDCl3): δ = 13.7 (d, J = 3.8 Hz), 45.1, 62.5,
90.6 (d, J = 197.2 Hz), 127.3, 128.5 (d, J = 3.8 Hz), 129.5 (d,
J = 3.8 Hz), 131.7, 163.8 (d, J = 20.1 Hz), 198.2 (d, J = 22.9 Hz).
1H NMR (300 MHz, CDCl3): δ = 2.3 (d, J = 4.2 Hz, 3 H, Me), 3.00
(d, J = 1.2 Hz, 3 H, Me), 3.11 (d, J = 1.5 Hz, 3 H, Me), 5.51 (d,
J = 50 Hz, 1 H, CHF).
13C NMR (75 MHz, CDCl3): δ = 26.0, 36.0, 36.9 (d, J = 4.4 Hz),
91.4 (d, J = 193.5 Hz), 163.6 (d, J = 19.8 Hz), 201.8 (d, J = 24.2
Hz).
HRMS (EI): m/z [M]+ calcd for C12H13FO3: 224.0849; found:
224.0845.
19F NMR (282 MHz, CDCl3): δ = –189.71 (d, J = 50 Hz).
Ethyl 4-(4-Chlorophenyl)-2-fluoro-3-oxobutanoate (2g)
Colorless oil; yield: 184 mg (71%, Table 2, entry 10).
Acknowledgment
1H NMR (300 MHz, CDCl3): δ = 1.26 (t, J = 7.2 Hz, 3 H, Me), 3.94
(d, J = 3.0 Hz, 2 H, CH2), 4.24 (q, J = 7.2 Hz, 2 H, CH2), 5.28 (d,
J = 48.9 Hz, 1 H, CHF), 7.10–7.30 (m, 4 H, HAr).
13C NMR (75 MHz, CDCl3): δ = 13.8 (d, J = 3.8 Hz), 44.3 (d,
J = 3.8 Hz), 62.6, 90.7 (d, J = 197.2 Hz), 128.7 (d, J = 3.1 Hz),
130.2 (d, J = 1.3 Hz), 131.0 (d, J = 3.8 Hz), 133.3, 163.7 (d,
J = 23.5 Hz), 197.9 (d, J = 22.9 Hz).
This work was partly supported by a Grant-in-Aid for Scientific Re-
search from the Ministry of Education, Culture, Sports, Science and
Technology of Japan (25410048).
Supporting Information for this article is available online at
m
tgioSrantnugIifoop
r
itmnatr
HRMS (EI): m/z [M]+ calcd for C12H12ClFO3: 258.0459; found:
258.0461.
References
2-Fluoro-1-phenylbutane-1,3-dione (2h)20
Colorless oil; yield: 151 mg (84%, Table 2, entry 13).
(1) (a) Olah, G. A.; Chambers, R. D.; Prakash, G. K. S. In
Synthetic Fluorine Chemistry; John Wiley: New York, 1992.
(b) Hudlicky, M.; Pavlath, A. E. In Chemistry of Organic
Fluorine Compounds II; American Chemical Society:
Washington, 1995. (c) Chambers, R. D. In Fluorine in
Organic Chemistry; Blackwell Publishing: Oxford, 2004.
(2) For recent reviews on hypervalent iodine compounds, see:
(a) Zhdankin, V. V. J. Org. Chem. 2011, 76, 1185.
(b) Merritt, E. A.; Olofsson, B. Synthesis 2011, 517.
(c) Brand, J. P.; González, D. F.; Nicolai, S.; Waser, J.
Chem. Commun. 2011, 47, 102. (d) Satam, V.; Harad, A.;
Rajule, R.; Pati, H. Tetrahedron 2010, 66, 7659. (e) Uyanik,
M.; Ishihara, K. Chem. Commun. 2009, 2086. (f) Zhdankin,
V. V. ARKIVOC 2009, (i), 1. (g) Zhdankin, V. V.; Stang, P.
J. Chem. Rev. 2008, 108, 5299.
(3) Yoneda, N. J. Fluorine Chem. 2004, 125, 7.
(4) Neumann, D.; Ruther, G. J. Fluorine Chem. 1980, 15, 213.
(5) Zupan, M.; Pollak, A. J. Chem. Soc., Chem. Commun. 1975,
715.
(6) Carpenter, W. J. Org. Chem. 1966, 31, 2688.
(7) (a) Sawaguchi, M.; Ayuba, S.; Hara, S. Synthesis 2002,
1802. (b) Arrica, M. A.; Wirth, T. Eur. J. Org. Chem. 2005,
395.
IR (KBr): 1736 (C=O), 1695 cm–1 (C=O).
1H NMR (300 MHz, CDCl3): δ = 2.34 (d, J = 4.2 Hz, 3 H, Me), 5.95
(d, J = 49 Hz, 1 H, CHF), 7.46–8.03 (m, 5 H, HAr).
13C NMR (75 MHz, CDCl3): δ = 25.9, 96.5 (d, J = 197.2 Hz), 128.7,
129.6 (d, J = 3.1 Hz), 133.4, 134.6, 190.2 (d, J = 19.1 Hz), 200.5 (d,
J = 23.5 Hz).
19F NMR (282 MHz, CDCl3): δ = –182.54 (dq, J = 4.2, 49 Hz).
2-Fluoro-1,3-diphenylpropane-1,3-dione (2i)20
Pale yellow crystals; yield: 233 mg (96%, Table 2, entry 15); mp
66.5–67.7 °C (hexane).
IR (KBr): 1701 (C=O), 1683 cm–1 (C=O).
1H NMR (300 MHz, CDCl3): δ = 6.54 (d, J = 49 Hz, 1 H, CHF),
7.43–7.50 (m, 4 H, HAr), 7.56–7.63 (m, 2 H, HAr), 8.07–8.10 (m, 4
H, HAr).
13C NMR (75 MHz, CDCl3): δ = 96.5 (d, J = 197.2 Hz), 128.7,
129.7 (d, J = 3.1 Hz), 133.5 (d, J = 1.8 Hz), 134.5, 191.1 (d,
J = 19.8 Hz).
19F NMR (282 MHz, CDCl3): δ = –188.20 (d, J = 49 Hz).
(8) Sawaguchi, M.; Hara, S.; Yoneda, N. J. Fluorine Chem.
2000, 105, 313.
(9) Chambers, R. D.; Greenhall, M. P.; Hutchinson, J.
Tetrahedron 1996, 52, 1.
(10) (a) Zajc, B.; Zupan, M. J. Chem. Soc., Chem. Commun.
1980, 759. (b) Yemul, S. S.; Kagan, H. B.; Setton, R.
4-Fluoroheptane-3,5-dione (2j)21
Colorless oil; yield: 45 mg (31%, Table 2, entry 17).
1H NMR (300 MHz, CDCl3): δ = 1.08 (t, J = 7.2 Hz, 6 H, Me),
2.49–2.82 (m, 4 H, CH2), 5.30 (d, J = 50 Hz, 1 H, CHF).
© Georg Thieme Verlag Stuttgart · New York
Synthesis 2013, 45, 3125–3130