7910
D. W. Knight et al. / Tetrahedron Letters 48 (2007) 7906–7910
7. Knight, D. W.; Redfern, A. L.; Gilmore, J. J. Chem. Soc.,
3.45–3.55 (1H, br s, OH), 3.89 (2H, q, J = 7.1 Hz, OCH2),
4.02–4.08 (1H, app. br s, 2-H), 4.29–4.34 (1H, app. br s,
3-H), 7.26 (2H, d, J = 8.3 Hz, 2 · ArH), 7.68 (2H, d,
J = 8.3 Hz, 2 · ArH); dC (CDCl3, 100 MHz) 14.2 (Me),
14.4 (Me), 22.1 (ArMe), 22.6 (CH2), 29.9 (CH2), 30.1
(CH2), 62.8 (OCH2), 70.1 (CH), 79.5 (4-C–I), 80.6 (CH),
128.1 (2 · ArCH), 130.4 (2 · ArCH), 134.5 (ArC), 144.2
(ArC), 170.2 (C@O); m/z (ES) 494 (M+H+, 45%), 476
(M+H+ꢀH2O, 100). [Found: M+H+, 494.0499.
C18H25INO5S requires M, 494.0498].
Perkin Trans. 1 2002, 622–628.
8. Journet, M.; Cai, D.; DiMichele, L.; Larsen, R. D.
Tetrahedron Lett. 1998, 39, 6427–6428.
9. Grandel, R.; Kazmaier, U. Eur. J. Org. Chem. 1998, 1833–
1840, and references cited therein.
10. Gridley, J. J.; Coogan, M. P.; Knight, D. W.; Malik, K.
M. A.; Sharland, C. M.; Singkhonrat, J.; Williams, S.
Chem. Commun. 2003, 2550–2551.
11. A typical procedure is as follows: (2SR,3RS)-Ethyl 5-
butyl-3-hydroxy-4-iodo-1-(4-toluenesulfonyl) 2,3-dihydro-
pyrrole-2-carboxylate 12; entry 2, Table 1: To a vigorously
stirred mixture of (2SR,3SR)-ethyl 2-(4-toluenesulfonyl-
amino)-3-hydroxynon-4-ynoate 11 (0.50 g, 1.36 mmol)10
and finely ground anhydrous potassium carbonate
(0.55 g, 4.1 mmol) in dry acetonitrile (12 ml) cooled in an
ice-water bath was slowly added a solution of iodine
(1.04 g, 4.1 mmol) in dry acetonitrile (20 ml). The resulting
purple suspension was stirred without further cooling for
16 h, then quenched by the addition of saturated aqueous
sodium thiosulfate, until the iodine colouration disap-
peared. The organic layer was separated and the aqueous
layer extracted with dichloromethane (3 · 15 ml). The
combined organic solutions were washed with brine
(20 ml), then dried (MgSO4), filtered through a plug of
silica gel and evaporated to leave essentially a pure
hydroxy-dihydropyrrole 12, entry 2, as a yellow oil
(0.625 g, 93%) which showed mmax (film) 3490, 1735,
12. For very early examples, see: Denss, R.; Girod, E.;
Hafliger, F.; Eugster, C. H. Helv. Chim. Acta 1959, 42,
1191–1193; More recent examples include: Gomez, A. M.;
Barrio, A.; Pedregosa, A.; Valverde, S.; Lopez, J. C.
Tetrahedron Lett. 2003, 44, 8433–8435; Chen, J. J.; Drach,
J. C.; Townsend, L. B. J. Org. Chem. 2003, 68, 4170–4178;
Peng, X.; Bondar, D.; Paquette, L. A. Tetrahedron 2004,
60, 9589–9598; Li, J.-S.; Chen, F.-X.; Shikiya, R.; Marky,
L. A.; Gold, B. J. Am. Chem. Soc. 2005, 127, 12657–
12665.
13. Knight, D. W.; Sharland, C. M. Synlett 2004, 119–121.
14. Fokin, V. V.; Sharpless, K. B. Angew. Chem., Int. Ed.
2001, 40, 3455–3457, and references cited therein; Muniz,
˜
K. Chem. Soc. Rev. 2004, 33, 160.
15. Herranz, E.; Sharpless, K. B. J. Org. Chem. 1978, 43,
2544–2548; For a direct method, see: Villar, A.; Ho¨vel-
mann, C. H.; Nieger, M.; Muniz, K. Chem. Commun.
˜
2005, 3304–3306.
1628, 1597, 1457, 1354, 1166, 1090, 1028, 912, 666 cmꢀ1
;
16. Wang, J. J.; Scott, A. I. Tetrahedron Lett. 1995, 36, 7043–
7046; For a general overview of this type of chemistry, see:
Li, J. J.; Gribble, G. W. Palladium in heterocyclic
chemistry. In Tetrahedron Organic Chemistry Series;
Pergamon Press: Oxford, 2000; Vol. 20.
dH (CDCl3, 400 MHz) 0.86 (3H, t, J = 7.2 Hz, 40-Me),
1.06 (3H, t, J = 7.1 Hz, OCH2Me), 1.27 (2H, hextet,
J = 7.2 Hz, 30-CH2), 1.41 (2H, quintet, J = 7.2 Hz, 20-
CH2), 2.33 (3H, s, ArMe), 2.56–2.66 (2H, m, 10-CH2),