10150
S. Hara et al. / Tetrahedron 68 (2012) 10145e10150
Science LTD: Hilversum, 2006; p 49; Selectfluor: (d) Singh, R. P.; Shreeve, J. M.
Acc. Chem. Res. 2004, 37, 31; (e) Nyffeler, P. T.; Duron, S. G.; Burkart, M. D.;
organic layer was washed with aq NaHCO3 and aq Na2S2O3, and
dried over MgSO4. After concentration under reduced pressure, 35a
was isolated by column chromatography (silica gel, hexane/CH2Cl2)
ꢀ
Vincent, S. P.; Wong, C.-H. Angew. Chem., Int. Ed. 2005, 44, 192 XtalFluos: (f)
Beaulieu, F.; Beauregard, L.-P.; Courchesne, G.; Couturier, M.; LaFlamme, F.;
L’Heureux, A. Org. Lett. 2009, 11, 5050; (g) L’Heureux, A.; Beaulieu, F.; Bennett,
C.; Bill, D. R.; Clayton, S.; LaFlamme, F.; Mirmehrabi, M.; Tadayon, S.; Tovell, D.;
Couturier, M. J. Org. Chem. 2010, 75, 3401 Fluolead: (h) Umemoto, T.; Singh, R.
P.; Xu, Y.; Saito, N. J. Am. Chem. Soc. 2010, 132, 18199; (i) Singh, R. P.; Umemoto, T.
J. Org. Chem. 2011, 76, 3113.
4. (a) Ayuba, S.; Yoneda, N.; Fukuhara, T.; Hara, S. Bull. Chem. Soc. Jpn. 2002, 75,
1597; (b) Ayuba, S.; Fukuhara, T.; Hara, S. Org. Lett. 2003, 5, 2873; (c) Ayuba, S.;
Hiramatsu, C.; Fukuhara, T.; Hara, S. Tetrahedron 2004, 60, 11445; (d) Hara, S.;
Aoyama, M. Synthesis 2008, 2510; (e) Fukuhara, T.; Hara, S. Synlett 2009, 198; (f)
Fukuhara, T.; Hara, S. J. Org. Chem. 2010, 75, 7393; (g) Tahara, R.; Fukuhara, T.;
Hara, S. J. Fluorine Chem. 2011, 132, 579; (h) Imagawa, Y.; Yoshikawa, S.; Fuku-
hara, T.; Hara, S. Chem. Commun. 2011, 9191.
in 78% yield; IR (neat) 3060, 1515, 1316, 1119 cmꢂ1 1H NMR
; d 8.19
(d, J¼8.5 Hz, 1H), 8.03 (d, J¼8.3 Hz, 1H), 7.93 (d, J¼8.0 Hz, 1H), 7.87
(d, J¼7.3 Hz, 1H), 7.65e7.49 (m, 3H); 19F NMR
d
ꢂ60.39 (s, 3F), (lit.20
ꢂ59.72), (s, 3F); 13C NMR
d 133.8, 132.7, 128.9, 128.7, 127.6, 126.6,
2
3
126.0 (q, JCeF¼30.5 Hz), 124.7 (q, JCeF¼5.7 Hz), 124.6 (q,
1JCeF¼273.4 Hz), 124.2 (q, 3JCeF¼2.6 Hz), 124.1.
4.8.2. 4-(Trifluoromethyl)-1,10-biphenyl (35b). White solid. Mp
68e69 ꢀC (lit.21 69e70 ꢀC); IR (KBr) 1614, 1334, 1116 cmꢂ1; 1H NMR
d
7.68 (s, 5H), 7.58e7.38 (m, 4H); 19F NMR
d
ꢂ63.83 (s, 3F); 13C NMR
5. As for the solid prepared from IF5 and Me4NF, see: Mahjoub, A. R.; Seppelt, K.
Angew. Chem., Int. Ed. Engl. 1991, 30, 323.
6. Previously, IF5eEt3Ne3HF was reported as a stable, non-hazardous, and easy to
handle reagent.4a,7 However, IF5eEt3Ne3HF is less stable than
IF5epyridineeHF, and decomposes in air under emitting HF.
d
144.7, 139.7, 129.3 (q, 2JCeF¼32.6 Hz), 129.0 (2C), 128.2, 127.4 (2C),
127.2 (2C), 125.7 (q, 3JCeF¼3.8 Hz, 2C), 124.3 (q, 1JCeF¼271.8 Hz).
7. Yoneda, N.; Fukuhara, T. Chem. Lett. 2001, 222.
4.8.3. Methyl 4-(trifluoromethyl)benzoate (35c). IR (neat) 2957,1731
8. IF5epyridineeHF is soluble in polar solvent, such as acetonitrile and DMF, and
poorly soluble in CH2Cl2 and hexane. However, in the polar solvents, the
fluorination reaction of 1 did not proceed.
(C]O), 1328, 1282, 1131 cmꢂ1; 1H NMR
d
8.16 (d, J¼8.0 Hz, 2H), 7.71
(d, J¼8.1 Hz, 2H), 3.96 (s, 3H); 19F NMR
d
ꢂ63.73 (s, 3F) (lit.22 ꢂ62.9 (s,
2
3F)); 13C NMR
d
165.8, 134.4 (q, JCeF¼32.9 Hz), 133.3, 129.9 (2C),
9. Structure of 10 was estimated from the chemical sift of that of a previously
reported similar compound, see: Brigaud, T.; Laurent, E. Tetrahedron Lett. 1990,
31, 2287.
125.4 (q, 3JCeF¼3.6 Hz, 2C), 123.6 (q, 1JCeF¼272.8 Hz), 52.5.
10.
X
þ/pyridineeHF(70%): (a) Sondej, S. C.; Katzenellenbogen, J. A. J. Org. Chem.
1986, 51, 3508; (b) Hird, M.; Toyne, K. J.; Slaney, A. J.; Goodby, J. W.; Gray, G. W. J.
Chem. Soc., Perkin Trans. 2 1993, 2337; (c) Prakash, G. K. S.; Hoole, D.; Reddy, V.
P.; Olah, G. A. Synlett 1993, 691; (d) Kuroboshi, M.; Hiyama, T. J. Fluorine Chem.
1994, 69, 127 Xþ/TBAþH2Fꢂ3 : (e) Kuroboshi, M.; Hiyama, T. Synlett 1991, 909
NOþ/pyridineeHF (70%): (f) York, C.; Prakash, G. K. S.; Olah, G. A. Tetrahedron
1996, 52, 9 Xþ/hexafluoropropene-diethylamine: (g) Shimizu, M.; Maeda, T.;
Fujisawa, T. J. Fluorine Chem. 1995, 71, 9 F2/I2: (h) Chambers, R. D.; Sandford, G.;
Atherton, M. J. Chem. Soc., Chem. Commun. 1995, 177; (i) Chambers, R. D.;
Sandford, G.; Sparrowhawk, M. E.; Atherton, M. J. J. Chem. Soc., Perkin Trans. 1
1996, 1941 Selectfluor/pyridineeHF (70%): (j) Reddy, V. P.; Alleti, R.; Peram-
buduru, M. K.; Welz-Biermann, U.; Buchholz, H.; Prakash, G. K. S. Chem. Com-
mun. 2005, 645 ArIF2: (k) Motherwell, W. B.; Wilkinson, J. A. Synlett 1991, 191
BrF3; (l) Sasson, R.; Hagooly, A.; Rozen, S. Org. Lett. 2003, 5, 769; (m) Cohen, O.;
Rozen, S. Tetrahedron 2008, 64, 5362; (n) Cohen, O.; Hagooly, Y.; Rozen, S.
Tetrahedron 2009, 65, 1361; (o) Hagooly, Y.; Rozen, S. Org. Lett. 2012, 14, 1114
Elecrochemical method: (p) Yoshiyama, T.; Fuchigami, T. Chem. Lett. 1992, 1995;
(q) Fuchigami, T.; Fujita, T. J. Org. Chem. 1994, 59, 7190; (r) Fujita, T.; Fuchigami,
T. Tetrahedron Lett. 1996, 37, 4725.
4.8.4. 1-Isobutyl-4-(trifluoromethyl)benzene (35d). IR (neat) 2960,
1327, 1124 cmꢂ1; 1H NMR
d
7.52 (d, J¼8.9 Hz, 2H), 7.25 (d, J¼8.9 Hz,
2H), 2.53 (d, J¼7.2 Hz, 2H), 1.92e1.85 (m, 1H), 0.91 (d, J¼6.5 Hz, 6H);
19F NMR
d
ꢂ62.87 (s, 3F); 13C NMR
d 145.8, 129.3 (2C), 128.0 (q,
2JCeF¼32.2 Hz), 125.0 (q, 3JCeF¼3.7 Hz, 2C), 124.4 (q,
1JCeF¼271.8 Hz), 45.2, 30.1, 22.2 (2C); HRMS (EI) calcd for C11H13F3
202.09693, found 202.09653.
4.8.5. 5-(Trifluoromethyl)benzo[d][1,3]dioxole (35e). IR (neat) 2911,
1449,1317,1265,1119 cmꢂ1; 1H NMR
d
7.14 (d, J¼8.2 Hz,1H), 7.03 (d,
J¼1.6 Hz, 1H), 6.86 (d, J¼8.2 Hz, 1H) 6.04 (s, 2H); 19F NMR
ꢂ62.03
d
(s, 3F) (lit.22 ꢂ61.3 (s, 3F)); 13C NMR
d 150.3, 147.9, 124.2 (q,
1
3
2JCeF¼33.2 Hz), 124.1 (q, JCeF¼270.9 Hz), 119.8 (q, JCeF¼4.1 Hz),
3
108.2, 105.8 (q, JCeF¼2.8 Hz), 101.9.
11. For the recent reviews of aromatic trifluoromethylation, see: (a) Tomashenko,
O. A.; Grushin, V. V. Chem. Rev. 2011, 111, 4475; (b) Roy, S.; Gregg, B. T.; Gribble,
G. W.; Le, V.-D.; Roy, S. Tetrahedron 2011, 67, 2161.
Acknowledgements
12. Ellison, R. A.; Woessner, W. D.; Williams, C. C. J. Org. Chem. 1972, 17, 2757.
13. Preparation of trifluoromethyl compounds from trialkyl oththothio esters: (a)
Matthews, D. P.; Whitten, J. P.; McCarthy, J. R. Tetrahedron Lett. 1986, 27, 4861
From dithiocarboxylate: (b) Zupan, M.; Bregar, Z. Tetrahedron Lett. 1990, 31,
3357; (c) Kuroboshi, M.; Hiyama, T. Chem. Lett. 1992, 827; (d) Furuta, S.; Kur-
oboshi, M.; Hiyama, T. Bull. Chem. Soc. Jpn. 1999, 72, 805; (e) Cohen, C.; Mishani,
E.; Rozen, S. Tetrahedron 2010, 66, 3579.
We are grateful to Asahi Glass Co., Ltd. for their donation of IF5.
References and notes
1. (a) Kirsh, P. In Modern Fluoroorganic Chemistry; Wiley-VCH: Weinheim, 2004;
ꢀ
ꢀ
14. Prokopcova, H.; Ramírez, J.; Fernandez, E.; Kappe, C. O. Tetrahedron Lett. 2008,
p
203; (b) Hiyama, T. In Organofluorine Compounds; Yamamoto, H., Ed.;
49, 4831.
Springer: Heidelberg, 2000; p 212; (c) Anderson, R. F.; Punderson, J. O. In Or-
ganofluorine Chemicals and Their Industrial Applications; Banks, R. E., Ed.; Ellis
Horwood LTD.: Chichester, UK, 1979; p 235.
15. Freskos, J. N. Synth. Commun. 1988, 18, 965.
16. Middleton, W. J. J. Org. Chem. 1975, 40, 574.
17. Fujikawa, K.; Fujioka, Y.; Kobayashi, A.; Amii, H. Org. Lett. 2011, 13, 5560.
18. Furuya, T.; Fukuhara, T.; Hara, S. J. Fluorine Chem. 2005, 126, 721.
19. Ray, F. E.; Albertson, C. E. J. Am. Chem. Soc. 1948, 70, 1954.
20. Xu, J.; Luo, D.-F.; Xiao, B.; Liu, Z.-J.; Gong, T.-J.; Fu, Y.; Liu, L. Chem. Commun.
2011, 4300.
2. Recent reviews and books on fluorination reagent, see: (a) Singh, R. P.; Shreeve,
J. M. Synthesis 2002, 2561; (b) Kirk, K. L. Org. Process Res. Dev. 2008, 12, 305; (c)
Al-Maharik, N.; O’Hagan, D. Aldrichimica Acta 2011, 44, 65; (d) Uneyama, K.
Organofluorine Chemistry; Blackwell: Oxford, 2006.
3. Air stable fluorination reagents. ArIF2: (a) Motherwell, W. B. Aldrichimica Acta
1992, 25, 71; (b) Sawaguchi, M.; Hara, S.; Yoneda, N. J. Fluorine Chem. 2000, 105,
313; (c) Hara, S. In Advances in Organic Synthesis; Laali, K. K., Ed.; Bentham
ꢀ
ꢀ
21. Kiss, A.; Hell, Z.; Balint, M. Org. Biomol. Chem. 2010, 8, 331.
22. Chu, L.; Qing, F.-L. Org. Lett. 2010, 12, 5060.