References
-
1a
Cintas P.
Synlett
1995,
1087
-
1b
Li C.-J.
Tetrahedron
1996,
52:
5643
-
1c
Li C.-J.
Chan TH.
Tetrahedron
1999,
55:
11149
-
1d
Chauhan KK.
Frost CG.
J. Chem. Soc., Perkin Trans. 1
2000,
3015
-
1e
Ranu BC.
Eur. J. Org. Chem.
2000,
2347
-
1f
Babu G.
Perumal PT.
Aldrichimica Acta
2000,
33:
16
-
1g
Podlech J.
Maier TC.
Synthesis
2003,
633
-
2a
Chauhan KK.
Frost CG.
Love I.
Waite D.
Synlett
1999,
1743
-
2b
Ali T.
Chauhan KK.
Frost CG.
Tetrahedron Lett.
1999,
40:
5621
-
2c
Abernethy CD.
Cole ML.
Davies AJ.
Jones C.
Tetrahedron Lett.
2000,
41:
7567
-
2d
Cooper IR.
Grigg R.
MacLachlan WS.
Sridharan V.
Thornton-Pett M.
Tetrahedron Lett.
2003,
44:
403
-
2e
Villalva-Servin NP.
Melekov A.
Fallis AG.
Synthesis
2003,
790
-
3a
Ranu BC.
Hajra A.
Jana U.
J. Org. Chem.
2000,
65:
6270
-
3b
Ranu BC.
Hajra A.
Jana U.
Tetrahedron Lett.
2000,
41:
531
-
3c
Ranu BC.
Samanta S.
Hajra A.
Synlett
2002,
987
-
3d
Ranu BC.
Das A.
Samanta S.
Synlett
2002,
727
-
3e
Ranu BC.
Dey SS.
Hajra A.
Tetrahedron
2002,
58:
2529
-
3f
Ranu BC.
Hajra A.
Dey SS.
Jana U.
Tetrahedron
2003,
59:
813
-
3g
Ranu BC.
Samanta S.
J. Org. Chem.
2003,
68:
7130
-
3h
Ranu BC.
Das A.
Hajra A.
Synthesis
2003,
1012
-
3i
Ranu BC.
Samanta S.
Tetrahedron
2003,
59:
7901
-
4a
Ohno H.
Hamaguchi H.
Tanaka T.
Org. Lett.
2000,
2:
2161
-
4b
Barros OSdR.
Lang S.
Oliveira CAFd.
Peppe C.
Zeni G.
Tetrahedron Lett.
2002,
43:
7921
-
4c
Barros OSdR.
Lang ES.
Peppe C.
Zeni G.
Synlett
2003,
1725
-
4d
Miyabe H.
Yamaoka Y.
Naito T.
Takemoto Y.
J. Org. Chem.
2004,
69:
1415
- 5
Ranu BC.
Mandal T.
Samanta S.
Org. Lett.
2003,
5:
1439
- 7
Peach ME.
The Chemistry of the Thiol Group
Part 2:
Patai S.
John Wiley;
New York:
1974.
p.721
-
8a
Devan N.
Sureshkumar D.
Beadham I.
Prabhu KR.
Chandrasekaran S.
Indian J. Chem.: Sect. B
2002,
41:
2112
-
8b
Ranu BC.
Dey SS.
Hajra A.
Tetrahedron
2003,
59:
2417 ; and references cited therein
-
8c
Srivastava N.
Banik BK.
J. Org. Chem.
2003,
68:
2109
-
8d
Yadav JS.
Reddy BVS.
Baishya G.
J. Org. Chem.
2003,
68:
7098
-
8e
Alam MM.
Varala R.
Adapa SR.
Tetrahedron Lett.
2003,
44:
5115
- 9
Cherkquaskas JP.
Cohen T.
J. Org. Chem.
1992,
57:
6
6
General Experimental Procedure; Representative Example for the Cleavage of Diphenyl Disulfide and Subsequent Reaction with Methyl Vinyl Ketone (Entry 2): Indium(I) iodide (121 mg, 0.5 mmol) was added to the solution of diphenyl disulfide (109 mg, 0.5 mmol) in freshly distilled THF (2.5 mL) under argon atmosphere followed by the addition of methyl vinyl ketone (70 mg, 1 mmol). The reaction mixture was heated under reflux for 2.5 h (TLC). THF was then evaporated off and the residue was quenched with water and extracted with Et2O (3 × 10 mL). The Et2O extract was washed with water and dried (Na2SO4). The aqueous extract containing indium derivatives was discarded although in relatively large-scale reactions indium salts may be recovered. Evaporation of the solvent left the crude product, which was purified by column chromatography over silica gel (hexane-Et2O, 95:5) to provide the pure addition product, 4-thiophenylbutan-2-one (155 mg, 86%) as a colorless liquid. IR (neat): 1716, 1477 cm-1. 1H NMR (300 MHz, CDCl3): δ = 2.14 (s, 3 H), 2.76 (t, J = 7.26 Hz, 2 H), 3.13 (t, J = 7.26 Hz, 2 H), 7.20-7.22 (m, 2 H), 7.26-7.35 (m, 3 H). 13C NMR (75 MHz, CDCl3): δ = 27.9, 30.5, 43.5, 126.7, 127.9, 129.4 (2 × C), 130.0 (2 × C). These values are in good agreement with those reported for this compound.9 Several Michael adducts are known and are identified by comparison of their spectroscopic data with those reported. The new compounds are characterized by their spectroscopic data and elemental analysis. These data for a few selective representative compounds are provided here.
Entry 8: IR (neat): 1475, 1716 cm-1. 1H NMR (300 MHz, CDCl3): δ = 1.27 (d, J = 6.51 Hz, 3 H), 2.12 (s, 3 H), 2.55 (dd, J
1 = 8.34 Hz, J
2 = 17.22 Hz, 1 H), 2.72 (dd, J
1 = 5.31 Hz, J
2 = 17.19 Hz, 1 H), 3.65 (m, 1 H), 7.26 (d, J = 8.61 Hz, 2 H), 7.33 (d, J = 8.61 Hz, 2 H). 13C NMR (75 MHz): δ = 20.9, 30.5, 38.4, 50.0, 129.0 (2 × C), 132.5, 133.4, 133.6 (2 × C), 206.2. Anal. Calcd for C11H13OClS: C, 57.76; H, 5.73. Found: C, 57.84; H, 5.81.
Entry 17: IR (neat): 1477, 1724 cm-1. 1H NMR (300 MHz, CDCl3): δ = 1.33 (d, J = 6.75 Hz, 3 H), 2.55-2.61 (m, 2 H), 3.13-3.19 (m, 1 H), 3.78 (s, 2 H), 7.24-7.33 (m, 5 H), 9.66 (s, 1 H). 13C NMR (75 MHz): δ = 21.3, 33.6, 35.2, 50.1, 127.1, 128.5 (2 × C), 128.7 (2 × C), 137.9, 200.5. Anal. Calcd for C11H14OS: C, 68.0; H, 7.26. Found: C, 68.09; H, 7.17.
Entry 20: Obtained as a mixture of diastereoisomers (59:41). IR (neat): 1475, 1724, 2721 cm-1. 1H NMR (300 MHz, CDCl3): δ = 1.04 (t, J = 7.17 Hz, 3 H), 1.20 (d, J = 7.21 Hz, 3 H), 1.62-1.73 (m, 2 H), 2.63-2.67 (m, 1 H), 3.34-3.40 (m, 1 H), 7.26 (d, J = 8.34 Hz, 2 H), 7.37 (d, J = 8.34 Hz, 2 H), 9.67 (d, J = 1.59 Hz, 1 H, minor), 9.68 (d, J = 0.98 Hz, 1 H, major). 13C NMR (75 MHz): δ = 9.7 (major), 10.2 (minor), 12.1 (major), 11.8 (minor), 26.2 (major), 24.2 (minor), 48.9 (major), 49.6 (minor), 52.9 (major), 51.7 (minor), 129.1 (2 × C), 133.4, 133.5 (2 × C), 133.6, 203.2. Anal. Calcd for C12H15OClS: C, 59.37; H, 6.23. Found: C, 59.41; H, 6.17.
Entry 24: IR (neat): 1477, 1737 cm-1. 1H NMR (300 MHz, CDCl3): δ = 2.59 (t, J = 7.5 Hz, 2 H), 3.13 (t, J = 7.5 Hz, 2 H), 3.67 (s, 3 H), 7.19-7.29 (m, 4 H). 13C NMR (75 MHz): δ = 29.7, 34.4, 52.3, 129.5 (2 × C), 131.8 (2 × C), 134.1, 134.2, 172.4. Anal. Calcd for C10H11O2ClS: C, 52.06; H, 4.77. Found: C, 52.11; H, 4.71.