H.-P. Cao et al. / Journal of Fluorine Chemistry 127 (2006) 1079–1086
1085
70 eV): m/z (%) = 412 (46) [M]+, 227 (100). Anal. Calcd. for
C18H9F8Cl: C, 52.38, H, 2.20. Found: C, 52.49; H, 2.12.
CDCl3): d = 111.50 (m, 2F), 125.57 (m, 2F), 139.24 (m, 1F),
167.68 (m, 1F). MS (EI, 70 eV): m/z (%) = 344 (100) [M]+, 345
(22). HRMS-EI: m/z [M]+ calcd. for C16H10F6N2: 344.07482.
Found: 344.07462.
4.4. Typical procedure for the cyclization reaction of 3
4g: white solid. IR (KBr): 1618, 1308, 1239, 1168, 1030,
Under a nitrogen atmosphere, 3a (1.71 g, 5 mmol), Na2S2O4
(4.35 g, 25 mmol), NaHCO3 (2.1 g, 25 mmol) and DMSO
(25 mL) was added to a 50 mL three-necked round bottomed
flask equipped with a magnetic stir bar and a condenser. The
mixture was then heated to 100 8C for 20 min with stirring. The
conversion of 3a was 100%, determined by 19F NMR. After
cooling, the mixture was poured into ice water (30 mL). The
aqueous layer was extracted with ether (3ꢁ 30 mL). The
combinedextractswerewashedwithwater(3ꢁ 20 mL)anddried
over Na2SO4. After removing ether, the residue was subjected to
column chromatography on silica gel to give 4a as a brown solid.
4a: brown solid. IR (KBr): 3226, 1516, 1208, 1124, 753,
676 cmꢀ1. 1H NMR (300 MHz, CDCl3): d = 6.73 (s, 2H), 4.00
(br, 4H). 19F NMR (282 MHz, CDCl3): d = 108.05 (m, 4F),
135.35 (m, 4F). MS (EI, 70 eV): m/z (%) = 306 (100) [M]+, 286
(33). Anal. Calcd. for C10H6F8N2: C, 39.23; H, 1.98; N, 9.15.
Found: C, 39.63; H, 2.11; N, 9.26.
1008, 972, 913, 776 cmꢀ1 1H NMR (300 MHz, CDCl3):
.
d = 8.04 (s, 1H), 7.95 (q, J = 8.4 Hz, 2H), 7.62 (d, J = 6.9 Hz,
2H), 7.50 (m, 3H). 19F NMR (282 MHz, CDCl3): d = 103.18
(m, 2F), 103.54 (m, 2F), 134.86 (m, 4F). MS (EI, 70 eV): m/z
(%) = 353 (17), 352 (100) [M]+. Anal. Calcd. for C16H8F8: C,
54.56; H, 2.29. Found: C, 54.86; H, 2.22.
4h: white solid. IR (KBr): 1281, 1181, 1114, 993, 829,
766 cmꢀ1. 1H NMR (300 MHz, CDCl3): d = 8.14 (m, 4H), 7.68
(t, J = 7.8 Hz, 2H). 19F NMR (282 MHz, CDCl3): d = 103.2 (m,
4F), 127.4 (m, 4F). MS (EI, 70 eV): m/z (%) = 326 (100) [M]+,
257 (41). Anal. Calcd. for C14H6F8: C, 51.55; H, 1.85. Found:
C, 51.87; H, 1.96.
4i: colorless oil. IR (film): 1619, 1261, 1193, 1169, 1014,
944 cmꢀ1
.
1H NMR (300 MHz, CDCl3): d = 7.64 (d,
J = 9.2 Hz, 1H), 6.95 (m, 2H), 3.09 (s, 6H). 19F NMR
(282 MHz, CDCl3): d = 100.4 (m, 2F), 104.0 (t, J = 7.4 Hz, 2F),
134.3 (m, 2F), 134.5 (m, 2F). MS (ESI): m/z = 320 [M + H]+.
HRMS-ESI: m/z [M + H]+ calcd. for C12H10F8N: 320.06855.
Found: 320.06800.
4b: white solid. IR (KBr): 1491, 1248, 1180, 1161, 1077,
1004, 945, 752 cmꢀ1. 1H NMR (300 MHz, CDCl3): d = 7.89 (d,
J = 8.1 Hz, 1H), 7.47 (m, 2H), 7.34 (m, 1H), 3.96 (s, 3H). 19F
NMR (282 MHz, CDCl3): d = 103.44 (m, 2F), 105.44 (m, 2F),
132.04 (m, 2F), 133.00 (m, 2F). MS (EI, 70 eV): m/z (%) = 330
(13), 329 (100) [M]+. Anal. Calcd. for C13H7F8N: C, 47.43; H,
2.14; N, 4.25. Found: C, 47.45; H, 2.19; N, 4.04.
4j: colorless oil. IR (film): 1619, 1297, 1226, 1190, 980,
923 cm-1. 1H NMR (300 MHz, CDCl3): d = 7.78 (d, J = 9.6 Hz,
1H), 7.28 (m, 2H), 3.94 (s, 3H). 19F NMR (282 MHz, CDCl3):
d = 101.5 (m, 2F), 103.6 (m, 2F), 134.5 (m, 4F). MS (EI,
70 eV): m/z (%) = 306 (100) [M]+, 287 (30). Anal. Calcd. for
C11H6F8O: C, 43.16; H, 1.98. Found: C, 42.85; H, 1.94.
4k: white solid. IR (KBr): 1510, 1261, 1191, 1153, 1008,
4c: brown oil. IR (film): 3474, 1310, 1272, 1174, 987,
968 cmꢀ1. 1H NMR (300 MHz, CDCl3): d = 9.10 (br, 1H), 7.12
(t, J = 2.0 Hz, 1H), 6.58 (s, 1H). 19F NMR (282 MHz, CDCl3):
d = 102.73 (m, 2F), 103.92 (m, 2F), 132.67 (m, 4F). MS (EI,
70 eV): m/z (%) = 265 (60) [M]+, 246 (32). HRMS-EI: m/z [M]+
calcd. for C8H3F8N: 265.01377. Found: 265.01474.
954, 815 cmꢀ1 1H NMR (300 MHz, CDCl3): d = 7.89 (d,
.
J = 8.1 Hz, 1H), 7.48 (m, 2H), 7.36 (m, 1H), 3.96 (s, 3H). 19F
NMR (282 MHz, CDCl3): d = 99.57 (m, 2F), 103.61 (m, 2F),
133.92 (m, 2F), 134.47 (m, 2F). MS (EI, 70 eV): m/z (%) = 329
(83) [M]+, 215 (58). Anal. Calcd. for C13H7F8N: C, 47.43; H,
2.14; N, 4.25. Found: C, 47.66; H, 2.29; N, 4.20.
4d: brown solid. IR (KBr): 3381, 1496, 1289, 1222,
986 cmꢀ1. 1H NMR (300 MHz, CDCl3): d = 7.06 (dd, J = 2.4,
9.0 Hz, 1H), 6.92 (d, J = 9.0 Hz, 1H), 5.77 (ddd, J = 4.5, 8.4,
48.9 Hz, 1H), 3.87 (s, 5H). 19F NMR (282 MHz, CDCl3):
d = 103.77 (ddd, J = 7.9, 16.5, 287.1 Hz, 1F), 113.77 (ddd,
J = 12.1, 22.6, 289.3 Hz, 1F), 122.99 (m, 1F), 129.10 (m, 1F),
133.77 (m, 1F), 143.94 (m, 1F), 186.28 (m, 1F). MS (EI,
70 eV): m/z (%) = 303 (100) [M]+, 288 (87). Anal. Calcd. for
C11H8F8NO: C, 43.58; H, 2.66; N, 4.62. Found: C, 44.06; H,
2.81; N, 4.29.
4l: white solid. IR (KBr): 1451, 1235, 1163, 1116, 992, 850,
763, 725 cmꢀ1 1H NMR (300 MHz, CDCl3): d = 8.73 (d,
.
J = 8.4 Hz, 2H), 8.56 (t, J = 4.2 Hz, 1H), 8.21 (m, 1H), 7.79 (m,
4H), 6.45 (m, 1H). 19F NMR: d = 98.06 (m, 1F), 106.02 (m, 1F),
123.20 (m, 1F),128.42 (m, 1F), 133.51 (m, 1F), 142.25 (m, 1F),
180.03 (m, 1F). MS (EI, 70 eV): m/z (%) = 359 (20), 358 (100)
[M]+. Anal. Calcd. for C18H9F7: C, 60.35; H, 2.53. Found: C,
60.53; H, 2.90.
4e: brown solid. IR (KBr): 3510, 1517, 1327, 1272, 1255,
1077, 1066, 1002 cmꢀ1. 1H NMR (300 MHz, CDCl3): d = 6.99
(d, J = 7.5 Hz, 1H), 6.89 (d, J = 7.5 Hz, 1H), 5.30 (d,
J = 14.7 Hz, 1H), 3.38 (m, 2H), 2.79 (t, J = 6.0 Hz, 2H),
1.91 (m, 2H). 19F NMR (282 MHz, CDCl3): d = 119.13 (d,
J = 7.1 Hz, 2F), 127.65 (m, 2F), 140.00 (m, 1F), 169.14 (m, 1F).
MS (EI, 70 eV): m/z (%) = 293 (99) [M]+, 292 (100). Anal.
Calcd. for C13H9F6N: C, 53.25; H, 3.09; N, 4.78. Found: C,
52.97; H, 3.24; N, 4.37.
Acknowledgment
We thank the National Science Foundation of China (Nos.
20272026, D20032010) for financial support of this work.
References
[1] (a) D.P. Curran, Synthesis (1988) 417–439;
4f: brown solid. IR (KBr): 3382, 1627, 1485, 1228, 979,
877 cmꢀ1. 1H NMR (300 MHz, CDCl3): d = 7.06 (m, 3H), 6.70
(m, 3H), 4.49 (br, 2H), 3.64 (br, 2H). 19F NMR (282 MHz,
(b) B.B. Snider, Chem. Rev. 96 (1996) 339–363;
(c) B. Giese, in: J.E. Baldwin (Ed.), Radicals in Organic Synthesis:
Formation of Carbon–Carbon Bonds, Pergamon Press, Oxford, 1986.