1172
B. Zagipa et al. / Journal of Fluorine Chemistry 128 (2007) 1168–1173
62.48, 123.68, 129.79, 130.2, 132.5, 153.67, 167.21; MS (EI),
m/z 264 (M+); HRMS, m/z calcd. for C11H12N4O2S 264.0681
and found: 264.0668.
5H); 13C NMR d 14.1, 60.6, 103.5 (d, J = 236.11Hz, CHF),
123.68, 129.79, 130.2, 132.5, 153.67, 167.21; 19F NMR d
ꢂ84.71 (d, JHF = 51.5 Hz); MS(EI), m/z 282 (M+), 264, 117,
106; HRMS, m/z calcd. for C11H11N4O2FS 282.0587 and
found: 282.0576.
4.2.6. a-[5-(1-Phenyltetrazolyl)thio]acetonitrile (6)
1H NMR d 4.24(s, 2H), 7.52–7.69 (m, 5H); MS (EI), m/z 217
(M+); HRMS, m/z calcd. for C9H7N5S 217.0422 and for
217.0413.
4.3.6. a-Fluoro-a-[5-(1-phenyltetrazolyl)thio]acetonitril e
(12)
1
Yellow oil. H NMR d 7.05 (d, J = 48.01 Hz, CHF), 7.45–
7.61 (m, 5H); 13C NMR d 91.3 (d, J = 231.65 Hz, CHF),
116.75, 123.6, 129.73, 129.9, 130.38, 151.67; 19F NMR d
ꢂ81.45 (d, JHF = 48.01 Hz); MS (EI), m/z 235 (M+), 207, 217,
149, 130; HRMS, m/z calcd. for C9H6N5FS 235.0328 and
found: 235.0309.
4.3. Electrolytic procedure for fluorination
A typical procedure is as follows. Anodic oxidation of 1
(0.5 mmol) was carried out in an undivided cell equipped with
platinum plate electrodes (2 cm ꢁ 1.5 cm) in 10 ml of 1 M
Et4NFꢀ4HF/dimethoxyethane or acetonitrile at room tempera-
ture. Constant current (10 mA/cm2) was passed and the reaction
was monitored by TLC. After electrolysis, the electrolytic
solution was passed through a short column filled with silica gel
using ethyl acetate as an eluent to remove fluoride salts. The
eluent was evaporated under reduced pressure, and the residue
was further purified by column chromatography on silica gel
using ethyl acetate to give pure fluorinated products. The
products were identified by spectroscopic data.
Acknowledgements
B. Zagipa is deeply indebted to UNESCO and the Japanese
Ministry of Education, Science, and Culture (Monbusho) for
granting her a research fellowship (2002–2003). We also thank
Morita Chemical Industries Co., Ltd., for generous gifts of
Et3Nꢀ3HF and Et4NFꢀnHF (n = 3, 4).
References
4.3.1. 1-Methyl-5-[(a-fluorobenzyl)thio]tetrazole (7)
1
Yellow oil. H NMR d 3.73 (s, 3H), 7.11 (d, J = 53.55 Hz,
[1] J.G. Allen, F.R. Atherton, M.J. Hall, C.H. Hassal, C.W. Holmer, R.W.
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CHF), 7.27–7.69 (m, 5H); 19F NMR
d
ꢂ68.88 (d,
J
HF = 53.6 Hz); MS (EI), m/z 224 (M+), 147, 109, 83; HRMS,
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4.3.2. Ethyl a-fluoro-a-[5-(1-methyltetrazolyl)thio]acetate
(8)
[5] B.G. Smith, G.C. Dezeny, D.L. Hughes, A.O. King, T.R. Verhoeven, J.
Org. Chem. 65 (1994) 8151–8156.
1
Colorless oil. H NMR d 1.33 (t, J = 7.02 Hz, 3H), 4.18 (s,
[6] (a) H. Hiyama (Ed.), Organofluorine Compounds, Springer-Verlag, Ber-
lin, 2000;
3H), 4.31 (q, J = 7.02 Hz, 2H), 6.49 (d, J = 50.1 Hz, CHF); 13
C
(b) R. Filler, Y. Kobayashi (Eds.), Biomedicinal Aspects of Fluorine
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NMR d 14.03, 29.69, 62.44, 92.08 (d, J = 239.27 Hz, CHF)
152.79, 167.23; 19F NMR d ꢂ82.45 (d, JHF = 50.05 Hz); MS
(EI), m/z 220 (M+), 202, 147, 84; HRMS, m/z calcd. for
C6H9N4O2FS 220.0430 and found: 220.0431.
(d) J.T. Welch (Ed.), Selective Fluorination in Organic and Bioorganic
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4.3.3. a-Fluoro-a-[5-(1-methyltetrazolyl)thio]acetonitrile
(9)
1
Yellow oil. H NMR d 4.12 (s, 2H), 6.92 (d, J = 48.02Hz,
(f) R.E. Banks, B.E. Smart, J.C. Tatlov (Eds.), Organofluorine Chemistry:
Principles and Commercial Applications, Plenum, New York, 1994.
[7] T. Fuchigami, in: P.S. Mariano (Ed.), Advances in Electron Transfer
Chemistry, vol. 6, JAI Press, CT, 1999, pp. 41–130.
CHF); 13C NMR d 33.88, 81.35 (d, J = 235.94 Hz, CHF),
110.68, 143.8; 19F NMR d ꢂ78.65 (d, JHF = 48.02 Hz); MS
(EI), m/z 173 (M+), 145, 115, 58. HRMS, m/z calcd. for
C4H4N5FS 173.0182 and found: 173.0182.
[8] T. Fuchigami, in: H. Lund, O. Hammerich (Eds.), Organic Electrochem-
istry, fourth ed., Marcel Dekker, New York, 2001 (Chapter 25).
[9] T. Fuchigami, T. Tajima, in: V.A. Soloshonok (Ed.), ACS Symposium
Series 911. Fluorine-Containing Synthesis, American Chemical Society,
Washington, 2005 (Chapter 15).
4.3.4. 1-Phenyl-[5-(a-fluorobenzyl)thio]tetrazole (10)
Yellow oil. 1H NMR d 7.24–7.58 (m, 10H), 6.91 (d,
J = 51.8 Hz, CHF); 19F NMR d ꢂ70.37 (d, JHF = 51.82 Hz);
MS (EI), m/z 286 (M+), 177, 166, 109; HRMS, m/z calcd. for
C14H11N4FS 286.0689 and found: 286.0695.
[10] T. Fuchigami, T. Tajima, in: V.A. Soloshonok, K. Mikami, T. Yamazaki,
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4.3.5. Ethyl a-fluoro-a-[5-(1-phenyltetrazolyl)thio]acetate
(11)
1
Colorless oil. H NMR d 1.34 (t, J = 6.85Hz, 3H), 4.37 (q,
J = 7.29Hz, 2H), 6.91 (d, J = 51.48 Hz, CHF), 7.54–7.95 (m,
[12] S. Higashiya, T. Sato, T. Fuchigami, J. Fluorine Chem. 87 (1998) 203–208.
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(1999) 7935–7939.
[14] Y. Hou, T. Fuchigami, Electrochem. Commun. 1 (1999) 445–448.