References
1a
Gerhartz W.
Yamamoto YS.
Kandy L.
Rounsaville JF.
Schulz G.
Ullmann’s Encyclopedia of Industrial Chemistry
5th ed., Vol. A9:
Verlag Chemie;
Weinheim:
1987.
p.531
1b
Rao AS. In Comprehensive Organic Synthesis
Vol. 7:
Trost BM.
Fleming I.
Ley SV.
Pergamon;
Oxford:
1991.
p.357
2a
De Vos D.
Bein T.
Chem. Commun.
1996,
917
2b
De Vos DE.
Sels BF.
Reynaers M.
Subba RaoYV.
Jacobs PA.
Tetrahedron Lett.
1998,
39:
3221
2c
Wentzel BB.
Gosling PA.
Feiters MC.
Nolte RJM.
J. Chem. Soc., Dalton Trans.
1998,
2241 ; and references cited therein
3a
Groves JT.
Quinn R.
J. Am. Chem. Soc.
1985,
107:
5790
3b
Liu C.-J.
Yu W.-Y.
Che C.-M.
Yeung C.-H.
J. Org. Chem.
1999,
64:
7365
3c
Cheung W.-H.
Yu W.-Y.
Yip W.-P.
Zhu N.-Y.
Che C.-M.
J. Org. Chem.
2002,
67:
7716 ; and references cited therein
4a
Horváth IT.
Rabái J.
Science
1994,
266:
72
4b
Juliette JJJ.
Horváth IT.
Gladysz JA.
Angew. Chem., Int. Ed. Engl.
1997,
36:
1610
For some excellent reviews on fluorous catalysis see:
5a
Cornils B.
Angew. Chem., Int. Ed. Engl.
1997,
36:
2057
5b
Curran DP.
Chemtracts Org. Chem.
1996,
9:
75
5c
Horváth IT.
Acc. Chem. Res.
1998,
31:
641
5d
de Wolf E.
van Koten G.
Deelman B.-J.
Chem. Soc. Rev.
1999,
28:
37
5e
Betzemeier B.
Knochel P.
Top. Curr. Chem.
1999,
206:
61
5f
Fish RH.
Chem.-Eur. J.
1999,
5:
1677
5g
Hope EG.
Stuart AM.
J. Fluorine Chem.
1999,
100:
75
5h
Rocaboy C.
Gladysz JA.
Actualité Chimique
2000,
9:
47
For some examples of oxidations in FBC see:
6a
Klement I.
Lütjens H.
Knochel P.
Angew. Chem.
1997,
109:
1605
6b
Betzemeier B.
Lhermitte F.
Knochel P.
Synlett
1999,
489
6c
Crich D.
Neelamkavil S.
J. Am. Chem. Soc.
2001,
123:
7449
6d
Cavazzini M.
Manfredi A.
Montanari F.
Quici S.
Pozzi G.
Eur. J. Org. Chem.
2001,
24:
4639
6e
ten Brink G.-J.
Vis JM.
Arends IWCE.
Sheldon RA.
Tetrahedron
2002,
58:
3977
6f
Legros J.
Crousse B.
Bonnet-Delpon D.
Bégué J.-P.
Tetrahedron
2002,
58:
3993
6g
Ragagnin G.
Betzemeier B.
Quici S.
Knochel P.
Tetrahedron
2002,
58:
3985
7a
Pozzi G.
Montanari F.
Quici S.
Chem. Commun.
1997,
69
7b
Yamada T.
Takai T.
Rholde O.
Mukaiyama T.
Chem. Lett.
1991,
1
7c
Yamada T.
Takai T.
Rholde O.
Mukaiyama T.
Chem. Lett.
1991,
5
8a
Höger S.
Bonrad K.
Mourran A.
Beginn U.
Möller M.
J. Am. Chem. Soc.
2001,
123:
5651
8b
Tsubata Y.
Suzuki T.
Miyashi T.
Yamashita Y.
J. Org. Chem.
1992,
57:
6749
9
Singh MP.
Sasmal S.
Lu W.
Chatterjee MN.
Synthesis
2000,
1380
10 Main isomer 7: 1-5% of the 5,7-diiodo isomer was also detected.
11 Analytical data for C29H9N3F34 (1): 1H NMR (400 MHz, CDCl3): δ = 8.73 (d, J = 4 Hz, 1 H), 8.51 (d, J = 7.8 Hz, 1 H), 7.89 (td, J = 7.8 and 1.6 Hz, 1 H), 7.87 (s, 1 H), 7.73 (s, 1 H), 7.42 (m, 1 H), 4.40 (s, 3 H) ppm. 13C NMR (100 MHz, CDCl3): δ = 148.6, 147.7, 137.2, 136.1, 136.0, 122.0-113.0(bm), 32.3, 28.7 ppm. 19F NMR (400 MHz, CDCl3): δ = -79.7 (s, 6 F), -107.4 (m, 4 F), -120.1 (s, 8 F), -120.7 (s, 8 F), -121.6 (s, 4 F), -125.0 (s, 4 F) ppm. IR (KBr, pellets): 3440 (m), 2922 (w), 2856 (w), 1635 (w), 1208 (s), 1150 (s), 666 (w) cm-1. MS (EI, 70 eV): m/e (rel. int.) = 1045 (100), 1025 (19), 967 (1), 706 (6), 676 (23), 626 (6), 338 (2), 307 (3), 258 (7), 168 (1). HRMS: calcd 1045.0254; found: 1045.0230. Mp 134 °C.
Analytical data for C33H17N3F34 (1a): 1H NMR (400 MHz, CDCl3): δ = 8.68 (d, J = 3.6 Hz, 1 H), 8.37 (d, J = 6.0 Hz, 1 H), 7.84 (td, J = 5.4 and 0.9 Hz, 1 H), 7.34 (m, 1 H), 7.15 (s, 1 H), 6.98 (s, 1 H), 4.25 (s, 3 H), 3.37 (m, 2 H), 3.06 (m, 2 H), 2.73 (m, 2 H), 2.45 (m, 2 H) ppm. 13C NMR (75 MHz, CDCl3): δ = 149.7, 149.6, 147.5, 139.5, 136.7, 135.8, 133.7, 130.4, 123.9, 123.8, 122.6, 121.6, 122.0-108.0 (m), 107.0, 32.7 (t), 31.8, 30.5 (t), 28.7 ppm. 19F NMR (400 MHz, CDCl3): δ = -79.7 (s, 6 F), -113.4 (s, 4 F), -120.5 (s, 4 F), -120.6 (s, 8 F), -120.8 (s, 4 F), -121.6 (s, 4 F), -122.3 (s, 4 F), -125.0 (s, 4 F). IR (KBr, pellets): 2961 (w), 1591 (w), 1470 (w), 1204 (s), 1150 (s), 724 (w), 659 (w) cm-1. MS (EI, 70 eV): m/e (rel. int.) = 1101 (100), 1082 (24), 732 (55), 682 (23), 668 (25), 355 (2), 334 (3), 281 (4), 207 (3). HRMS: calcd.1101.088; found: 1101.044. Mp 104 °C.
12
Typical Procedure: Preparation of cyclooctene oxide (3a):
A 50 mL Schlenk tube, equipped with a stirrer and a O2-inlet was charged with the fluorous benzimidazole 1 (52.0 mg, 50 µmol, 2 mol%) dissolved in perfluorooctyl bromide (2.5 mL), and RuCl3·xH2O (36% Ru, 7 mg, 25 µmol, 1 mol%) dissolved in a few drops of acetone leading to a red solution. After stirring for 0.5 h, a solution of cis-cyclooctene (220 mg, 2.0 mmol) and i-PrCHO (288 mg, 4.0 mmol, 2 equiv) in chlorobenzene (2 mL) was added. The biphasic reaction mixture was stirred at 40 °C while a gentle stream of oxygen from a balloon was passing. The color of the reaction mixture changes from red to deep blue within 15 min. At the end of the reaction, the mixture was cooled to 10 °C, the organic layer was decanted and the fluorous phase was washed with chlorobenzene (4 × 2 mL). The chlorobenzene is removed in vacuo and the residue diluted with CH2Cl2 (20 mL). The organic phase is treated with cold NaOH (0.1 M, 20 mL) and washed with brine. After drying (MgSO4), filtration and evaporation of the solvent in vacuo the crude product was purified by flash chromatography (eluent: Et2O-pentane), yielding 224 mg (89%) of analytically pure cyclooctene oxide. The blue fluorous phase containing the Ru-catalyst was used directly for further reaction runs without loss of activity.
