A. L. Krasovsky et al. / Tetrahedron Letters 45 (2004) 1129–1132
1131
N
CH2Cl2
N
N
COCF3
SO2Ph
COCF3
SO2Ph
CH2Cl2, 0 °C
74%
∆, 24h
PhSO2
77%
CF3
6
7
O
PhSO2
PhSO2
mixture of diastereomers 4.3 / 1
H
N
H
N
3
N
H
COCF3
Et3N
COCF3
SO2Ph
CH2Cl2, 0 °C
89%
rt, 2h
93%
PhSO2
SO2Ph
8
9
mixture of diastereomers 6.7 / 1
Scheme 3.
10. Pouzet, P.; Erdelmeier, I.; Ginderow, D.; Mornon, J.-P.;
Dansette, P.; Mansuy, D. J. Chem. Soc., Chem. Commun.
1995, 473; Pouzet, P.; Erdelmeier, I.; Ginderow, D.;
Mornon, J.-P.; Dansette, P.; Mansuy, D. J. Heterocycl.
Chem. 1997, 34, 1567; Ho, M. T.; Treiber, A.; Dansette, P.
Tetrahedron Lett. 1998, 39, 5049–5052; Lu, Y.; Lemal, D.
M.; Jasinski, J. P. J. Am. Chem. Soc. 2000, 122, 2440–
2445.
CF3
CF3
O
PhSO2
PhSO2
O
+
SO2Ph
Scheme 4.
11. Preparation of b-trifluoroacetylketene diphenyldithioacetal
tetroxide 3: To a solution of the b-trifluoroacetylketene
S,S-acetal 18 (10 mmol) in TFA (15 mL), a mixture of
trifluoroacetic anhydride (10 mL) and 98–99% hydrogen
peroxide (60 mmol) was added at 0 °C. The solution was
stirred at 0 °C for 3 h. Removal of the solvent under
reduced pressure at 0 °C afforded the product as the light-
brown oil that was used for the further reactions without
This work is in progress in our laboratory and the
results will be reported in due course.
Acknowledgements
The research described in this publication was supported
by the Russian Fundamental Investigation Foundation
(Grant 03-03-32024-a).
1
additional purification. H NMR (400 MHz, CDCl3) 7.52
(m, 4H, m-Ph), 7.62 (m, 2H, p-Ph), 7.81 (m, 4H, o-Ph),
8.01 (s, 1H, @CAH). 13C NMR (400 MHz, CDCl3) 114.6
(q, CF3, J 290.3 Hz), 129.7, 130.1, 135.9, 136.2, 137.5,
138.1, 142.2, 153.4, 182.7 (q, C@O, J 40.9 Hz). Found: C,
47.07; H, 2.41; Anal. Calcd for C16H11F3O5S2: C, 47.52%;
H, 2.74%.
References and notes
12. Highly concentrated H2O2 was obtained according to:
Giguere, P. A. Bull. Chem. Soc. Fr. 1954, 720.
1. Chemistry of Organic Fluorine Compounds: An Update;
Hudlicky, M.; Pavlath A. E., Eds.; ACS Monograph
Series N 187; American Chemical Society: Washington,
DC, 1995.
2. Filler, A.; Kobayashi, Y. Biomedical Aspects of Fluorine
Chemistry; Kodansha Ltd.: Tokyo, 1981.
3. Krasovsky, A. L.; Nenajdenko, V. G.; Balenkova, E. S.
Russ. Chem. Bull. 2001, 8, 1329–1333.
4. Krasovsky, A. L.; Nenajdenko, V. G.; Balenkova, E. S.
Russ. Chem. Bull. 2002, 11, 1925–1930.
13. General procedure for the reaction of b-trifluoroacetyl-
ketene diphenyldithioacetal tetroxide 3 with aromatics: To
a solution of 3 (5 mmol) in dichloromethane (20 mL) the
aromatic compound (6 mmol) in dichloromethane (20 mL)
was added at rt (in the case of 2-methylindole and N-
methylpyrrole at 0 °C). Then the reaction mixture was
stirred at rt for the appropriate time (TLC control). The
organic solvents were removed in vacuo. The products
were purified by column chromatography (silica gel,
hexane).
5. Nenajdenko, V. G.; Krasovsky, A. L.; Lebedev, M. V.;
Balenkova, E. S. Synlett 1997, 12, 1349.
Selected spectra E-4a: yellow crystals, mp 147–150 °C
(dec.) 1H NMR (400 MHz, CDCl3) 3.63 (s, 3H, CH3); 3.85
(s, 3H, CH3); 6.38 (br s, 1H); 6.55 (br d, 1H, J 8.8 Hz); 7.33
(br d, 1H, J 8.8 Hz); 7.53 (br t, 2H, J 7.5 Hz); 7.62 (br t,
1H, J 7.3 Hz); 7.90 (br d, 2H, J 7.3 Hz); 8.12 (br s, 1H,
@CH). Found: C, 53.73; H, 3.61; Anal. Calcd for
C18H15F3O5S: C, 54.00%; H, 3.78%.
6. Krasovsky, A. L.; Hartulyari, A. S.; Nenajdenko, V. G.;
Balenkova, E. S. Synthesis 2002, 1, 133–137; Krasovsky,
A. L.; Moiseev, A. M.; Nenajdenko, V. G.; Balenkova,
E. S. Synthesis 2002, 7, 901–905; Krasovsky, A. L.;
Nenajdenko, V. G.; Balenkova, E. S. Synthesis 2002,
1379–1384; Arcady, L.; Krasovsky, A. L.; Moiseev, A. M.;
Nenajdenko, V. G.; Balenkova, E. S. Khem. Get. Soed.
2002, 2, 253–256.
7. Krasovsky, A. L.; Nenajdenko, V. G.; Balenkova, E. S.
Tetrahedron 2001, 57, 201–209.
8. Hojo, M.; Masuda, R. J. Org. Chem. 1975, 40, 963–965.
9. Krasovsky, A. L.; Pissarev, S. A.; Nenajdenko, V. G.;
Balenkova, E. S. J. Chem. Soc., Perkin Trans. 1 2002,
2554–2560.
8 white crystals, mixture of diastereomers a/b 6.7/1, mp
1
123–124 °C H NMR (CDCl3) 2.51 (s, 3H, a+b); 5.36 (d,
1H, J 11.9 Hz, a); 5.42 (d, 1H, J 11.7 Hz, b); 5.73 (d, 1H, J
11.7 Hz, b); 5.86 (d, 1H, J 11.9 Hz, a); 6.57 (br t, 1H, J
7.6 Hz, a); 6.65–7.30 (m, 9H, Ph+indole, a+b), 7.62 (br t,
2H, J 7.7 Hz, Ph, a+b); 7.71 (br t, 1H, J 7.4 Hz, Ph, a+b);
7.93 (br s, 1H, NH, b); 8.04 (d, 1H, J 7.5 Hz, Ph, b); 8.09
(d, 1H, J 7.5 Hz, Ph, a); 8.38 (br s, 1H, NH, a). Found: C,