736
C.-J. Li, D.-L. Chen
LETTER
(10) For reviews on indium-mediated reactions, see: Cintas, P.
Synlett, 1995, 1087; Hashmi, A.S.K. J. Prakt. Chem., Chem.
Zeit. 1998, 340, 84.
(11) Krapcho, A. P.; Diamanti, J.; Cayen, C.; Bingham, R. Org.
Synth. Coll.Vol .V, 198.
(3) Anderson, D. M. Sci. Am. 1994, 271, 62. For a total synthesis,
see: Nicolaou, K. C.; Rutjie, F. P. J. T.; Theodorakis, E. A.;
Tiebes, J.; Sato, M.; Untersteller, E. J. Am. Chem. Soc. 1995,
117, 1173.
(4) Tomita, K.; Sato, S.; Kobayashi, S. (Sankyo Co.) Jpn. Kokai
Tokkyo Koho JP 60,132,972 [85,132,972] (Cl. C07D285/00),
16 Jul 1985, Appl. 83/242,935, 22 Dec 1983; Chem. Abstr.
1987, 107, 96749c.
(5) For an excellent review of eight-membered ring synthesis,
see: Petasis, N. A.; Patane, M. A. Tetrahedron 1992, 48, 5757.
For a review on eight-membered ring ether synthesis, see:
Moore, J. A.; Anet, F. A. L. in Comprehensive Heterocyclic
Chemistry; Eds. Katritzky, A. R., Rees, C. W.
(12) Compound 8: To a mixture of 6 (312 mg, 1.66 mmol) and NaH
(72 mg, 60%, 1.8 mmol) in DMF(5 mL), 1,4-dibromo-2-
butene (533 mg, 2.5 mmol) in DMF (2 mL) was added. The
reaction mixture was stirred for 30 min, then quenched by 0.1
N HCl. The product was extracted with ether (3x20 mL),
washed with saturated aq. NdHCO3 (3x10 mL) and water
(3x10 mL), dried over MgSO4 and filtered. The solvent was
removed under vacuum. Flash chromatography gave ethyl 3-
(4-bromo-2-buten-1-yl)-4-oxo-tetrahydrothiopyran-3-
carboxylate (8) (85 mg, 16% yield). FTIR(film): 2978, 2913,
1715, 1425, 1206, 978 cm-1. 1H NMR(200Mz, CDCl3, ppm):
d 5.70-5.73(m, 2H), 4.18-4.23(m, 2H), 3.85(d, 2H), 3.21(m
(6) For recent reviews, see: Dowd, P.; Zhang, W. Chem. Rev.
1993, 93, 2091.
(7) For recent reviews, see: Jasperse, C. P.; Curran, D. P.; Fevig,
T. L. Chem. Rev. 1991, 91, 1237; Motherwell, W, B.; Crich,
D. Best Synthetic Methods, Free Radical Chain Reactions in
Organic Synthesis: Academic Press: London, 1991; Giese, B.;
Radicals in Organic Synthesis: Pergamon: Oxford, 1986;
Hart, D. J. Science 1984, 233, 883.
(8) For recent reviews, see: Hesse, M. Ring Enlargement in
Organic Chemistry; VCH: Weinheim, 1991. Stach, H.; Hesse,
M. Tetrahedron 1988, 44, 1573; Roxburgh, C. J. Tetrahedron
1993, 49, 10749. Gutsche, C. D.; Redmore, D. Carbocyclic
Ring Expansion Reactions; Academic Press: New York, 1968;
Haufe, G.; Mann, G. Chemistry of Alicyclic Compounds:
Structure and Chemical Transformations; Elsevier Science
Publishers: Amsterdam, 1989; Wovkulich, P. M.
Comprehensive Organic Synthesis; Trost, B. M., Fleming, I.
Eds.; Pergamon: Oxford, 1991; Vol. 1, Chapter 3.3.
(9) Li, C. J.; Chen, D. L.; Lu, Y. Q.; Haberman, J. X.; Mague, J.
T. J. Am. Chem. Soc. 1996, 118, 4216; Haberman, J. X.; Li, C.
J. Tetrahedron Lett. 1997, 38, 4735; Li, C. J.; Chen, D. L.; Lu,
Y. Q.; Haberman, J. X.; Mague, J. T. Tetrahedron 1998, 54,
2347. For reviews on such reactions, see: Li, C. J.
1H), 2.60-2.95(m, 6H), 2.41-2.43(m, 1H), 1.25(t, 3H). 13
C
NMR(100Mz, CDCl3, ppm): d 205.2, 170.8, 130.6, 130.2,
62.7, 61.8, 42.90, 37.6, 36.9, 32.0, 30.4, 14.0. .
(13) Compound 10: A mixture of water (3 mL), ether (2 mL), 8
(100 mg, 0.311 mmol), and indium powder (37 mg, 0.32
mmol) was stirred at r.t. for 12h. The reaction was quenched
by 0.1N HCl, extracted by ether (3x10 mL), washed by
saturated aq. NaHCO3 (3x10 mL) and water (3x19 mL), dried
over MgSO4, and filtered. The filtrate was concentrated in
vacuo. The residue was dissolved in THF (5 mL) and was
treated with DBU (5 mg) at room temperature for 12h. Flash
chromatography on silica gel (eluent: hexane/EtOAc=15:1)
gave ethyl 5-ethylidene-1-thiacyclohexan-6-one-3-
carboxylate (10) (47 mg, 62% yield). FTIR(film): 2978, 1734,
1684, 1616, 1464, 1425, 1181, 1036, 864 cm-1. 1H NMR(400
MHz, CDCl3, ppm): d 6.76(q, 1H), 4.15(m 2H), 3.05-3.19(m,
4H), 2.64-2.87(m, 4H), 2.43(m, 1H),1.83(d, 3H), 1.26(t, 3H).
13C NMR(100 MHz, CDCl3, ppm): d 203.98, 172.77, 138.24,
138.00, 60.93, 45.49, 42.91, 32.86, 32.76, 25.11, 14.26, 14.16.
Anal. Calc’d. for C12H18O3S: C, 59.48; H, 7.49. Found: C,
59.07; H, 7.57.
Tetrahedron, 1996, 52, 5643; Li, C. J.; Chan, T. H. Organic
Reactions in Aqueous Media, John Wiley & Sons, New York
1997; Li, C. J. Chem. Rev. 1993, 93, 2023; Paquette, L. A. In
Green Chemistry: Frontiers in Benign Chemical Synthesis
and Processing; Anastas, P.; Williamson, T. Eds, Oxford
University Press: Oxford, 1998; Lubineau, A.; Auge, J.;
Queneau, Y. in Organic Synthesis in Water, ed. Grieco, P. A.
Blackie Academic & Professional, Glasgow, 1998.
Article Identifier:
1437-2096,E;1999,0,06,0735,0736,ftx,en;G08399ST.pdf
Synlett 1999, No. 6, 735–736 ISSN 0936-5214 © Thieme Stuttgart · New York