M. M e debielle et al. / Tetrahedron 56 (2000) 2655±2664
2663
1
2
108.7 (2F, CF a), 2123.4 (2F, CF b), 2126.3 (2F, CF g).
2
(1H, ±NH, broad singlet). GC/Mass: m/e489 (M ), 470
2
2
1
1
1
(M 2HF), 430 (M 2CH CO H), 416 (M 2CH CO Me).
1
H NMR (CDCl ): d 4.06 (2H, CH , broad singlet), 7.32±
3
H
2
2 2 2 2
7
8
3
.45 (3H, m, arom H), 7.69 (1H, d, J8.21 Hz, arom H),
1
48 (M 2CO H). Analysis: Calcd C 42.76, H 2.05, N 3.56.
Analysis: Calcd C 41.73, H 2.27, N 2.86. Found. C 41.66, H
2.12, N 2.55.
1
.50 (1H, ±NH, broad singlet). GC/Mass: m/e393 (M ),
2
3
8
Found. C 42.64, H 2.44, N 3.48.
2-Tri¯uoromethyl-indole-3-acetic acid 20. Same pro-
cedure as for the preparation of compound 16. The
electrolysis was stopped after 535 C. The electrolysis solu-
tion was poured into water (400 ml) and extracted with
EtOAc (3£200 ml). The combined organic layers were
2-Nona¯uorobutyl-indole-3-acetic acid methyl ester 28.
Same procedure as in the case of compound 27 (K CO was
used as base; see text). The crude product was puri®ed by
silica gel chromatography (Hexane±EtOAc 75:25) to give
28 in 32% yield (0.38 g; 0.93 mmol) as a yellowish viscous
oil (slowly solidi®es on standing). TLC (Hexane±EtOAc
2
3
washed with water (5£400 ml), dried over MgSO and
4
®ltered. Evaporation of solvent left unreacted catalyst.
Aqueous solution was acidi®ed (pH 5) with concentrated
1
9
7
2
5:25): R 0.50. F NMR (CDCl ): d 281.4 (3F, CF ),
HCl and extracted with CHCl (3£200 ml). The combined
f
3
F
3
3
108.8 (2F, CF a), 2123.4 (2F, CF b), 2126.3 (2F, CF g).
2
organic extracts were washed with water (3£200 ml) and
2
2
1
H NMR (CDCl ): d 3.56 (3H, CH , singlet), 3.92 (2H,
dried over MgSO . Evaporation of the solvent left a
4
3
H
3
CH , broad singlet), 7.32±7.45 (3H, m, arom H), 7.69 (1H,
2
brown solid as crude product which was puri®ed by silica
gel chromatography with hexane±EtOAc (70:30) as ®rst
eluent to recover benzo[c]quinoline, and then with hexane±
EtOAc (50:50) to give 0.51 g of 20 as a yellowish solid.
d, J8.21 Hz, arom H), 8.49 (1H, ±NH, broad singlet). GC/
1
1
Mass: m/e407 (M ), 362 (M 2CO H). Analysis: Calcd C
2
44.24, H 2.48, N 3.44. Found. C 44.54, H 2.58, N 3.65.
1
9
TLC (Hexane±EtOAc 55:45): R 0.50.
F
NMR
f
1
2-Nona¯uorobutyl-indole-3-butyric acid 29. Same pro-
cedure as in the case of compound 27. The crude product
was puri®ed by silica gel chromatography (Hexane±EtOAc
75:25) to give 29 in 48% yield (0.58 g; 1.38 mmol) as a
yellowish viscous oil. TLC (Hexane±EtOAc 70:30):
(CDCl ): d 281.3 (3F, CF ). H NMR (CDCl ):
3
F
3
3
d 3.92 (2H, CH , broad singlet), 7.32±7.45 (3H, m,
H
2
arom H), 8.07 (1H, d, J8.21 Hz, arom H), 8.49 (1H,
1
±NH, broad singlet). GC/Mass: m/e243 (M ), 198
1
(M 2CO H). Analysis: Calcd C 54.33, H 3.32, N 5.76.
Found. C 54.46, H 3.58, N 5.85.
2
1
9
R 0.50.
F NMR (CDCl ): d 281.4 (3F, CF ),
109.2 (2F, CF a), 2123. 3 (2F, CF b), 2126.0 (2F,
2 2
1
f
3
F
3
2
CF g). H NMR (CDCl ): d 2.11 (2H, CH , m), 2.46
2
3
H
2
(
2H, CH , t), 2.83 (2H, CH , m), 7.00±7.37 (3H, m, arom
2
Acknowledgements
2
H), 7.62 (1H, d, J7.84 Hz, arom H), 7.93 (1H, ±NH, broad
1
1
singlet). GC/Mass: m/e421 (M ), 348 (M 2CH CO H).
M. M. would like to thank the CNRS for ®nancial funding as
well as the Agency of Industrial Science and Technology
(AIST, Japan) for a fellowship. K. K. and S. F. would like to
thank the AIST for travel grants to Paris.
2
2
Analysis: Calcd C 45.62, H 2.87, N 3.32. Found. C 45.42, H
2.81, N 3.55.
2-Nona¯uorobutyl-4,4,4-tri¯uoro-3-(indol-3-yl)butyric
acid 30. Same procedure as in the case of compound 27. The
crude product was puri®ed by silica gel chromatography
(
References
Hexane±EtOAc 80:20) to give 30 in 35% yield (0.48 g;
.01 mmol) as a yellowish viscous oil. TLC (Hexane±
1
1. Rossi, R. A.; Pierini, A. B.; Palacios, S. M. Nucleophilic Substi-
tution by the SRN1 Mechanism on Alkyl Halides. Advances in Free
Radical Chemistry; Tanner, D. D., Ed.; JAI Press: Greenwich, CT,
1990, pp 193±252.
1
9
EtOAc 80:20): R 0.50. F NMR (CDCl ): d 271.3
f
3
F
(
CF a), 2122.6 (2F, CF b), 2126.0 (2F, CF g). H NMR
3F, d, J9.03 Hz, CF ), 281.7 (3F, CF ), 2110.03 (2F,
2 2 2
3
3
1
(
3
CDCl ): d 2.95±3.00 (1H, dd, J16.5, 9.2 Hz), 3.08±
2. Sav e ant, J-M. Tetrahedron 1994, 50, 10117.
3
H
.14 (1H, dd, J16.5, 5.4 Hz), 4.24 (1H, ±CHCF , ddq,
3. Lablache-Combier, A. Heteroaromatics. Photoinduced
Electron Transfer; Fox, M. A., Chanon, M., Eds.; Elsevier: New
York, 1988, p 134 Part C, Chapter 4-4.
3
J9.1, 6.2, 1.2 Hz), 7.14±7.27 (3H, m, arom H), 7.82
(
1H, d, J7.80 Hz, arom H), 8.03 (1H, ±NH, broad singlet).
2 2
1
1
3
GC/Mass: m/e475 (M ), 416 (M 2CH CO H). Analysis:
4. Bowman, W. R. Photoinduced nucleophilic substitution at sp
carbon. Photoinduced Electron Transfer; Fox, M. A., Chanon, M.
Eds.; Elsevier: New York, 1988, pp 487±534 Part C, Chapter 4±8.
Calcd C 40.44, H 1.91, N 2.95. Found. C 40.62, H 2.02, N
2.65.
5
. M e debielle, M.; Pinson, J.; Sav e ant, J.-M. Electrochimica Acta
1997, 42, 2049.
2
-Nona¯uorobutyl-4,4,4-tri¯uoro-3-(indol-3-yl)butyric
acid methyl ester 31. Same procedure as in the case of
compound 27. The crude product was puri®ed by silica
gel chromatography (Hexane±EtOAc 80:20) to give 31 in
6. M e debielle, M. J.; Pinson, J.; Oturan, M. A.; Sav e ant, J.-M.
J. Org. Chem. 1996, 61, 1331.
7. M e debielle, M. Tetrahedron Lett. 1996, 37, 5119.
8. Burkholder, C.; Dolbier Jr, W. R.; M e debielle, M. J. Org.
Chem. 1998, 63, 5385.
9. Burkholder, C.; Dolbier Jr, W. R.; M e debielle, M. Tetrahedron
Lett. 1998, 39, 8853.
10. Burkholder, C.; Dolbier Jr, W. R.; M e debielle, M. J. Fluorine
Chem. 1999, 95, 127.
2
8% yield (0.39 g; 0.81 mmol) as a yellowish viscous oil.
1
9
TLC (Hexane±EtOAc 80:20): R 0.50. F NMR (CDCl3):
f
d 271.2 (3F, d, J9.03 Hz, CF ), 281.7 (3F, CF ),
F
3
3
2
110.03 (2F, CF a), 2122.6 (2F, CF b), 2126.0 (2F,
2 2
1
CF g). H NMR (CDCl ): d 2.93±2.99 (1H, dd,
2
3
H
J16.5, 9.2 Hz), 3.07±3.13 (1H, dd, J16.5, 5.4 Hz),
4
.24 (1H, ±CHCF , ddq, J9.1, 6. 2, 1.2 Hz), 7.14±7.27
11. Gong, Y.; Kato, K.; Kimoto, H. Tetrahedron Lett. 1999, 40,
5743.
3
(
3H, m, arom H), 7.79 (1H, d, J7.86 Hz, arom H), 8.03