Abstract
Enantioselective intramolecular iodoetherification of disubstituted γ-hydroxyalkenes has been intended using NIS in the presence of 0.2 equivalents of (R )-Binol-Ti(IV) complex to procure the corresponding tetrahydrofurans in up to 65% ee.
Key words
reagent-controlled - iodocyclization - γ-hydroxyalkenes - (R )-Binol-Ti(IV) complex -
N -iodosuccinimide
References
1a Rousseau G.
Robin S.
Tetrahedron
1998,
54:
13681
1b Harding KE.
Tinger TH. In Comprehensive Organic Synthesis
Vol. 4:
Trost BM.
Fleming I.
Pergamon;
Oxford:
1991.
p.463
1c Mulzer J. In Organic Synthesis Highlights
VCH;
Weinheim:
1991.
p.157
2a Fuji K.
Node M.
Naniwa Y.
Kawabata T.
Tetrahedron Lett.
1990,
31:
3175
2b Furth M.
Brown EG.
J. Am. Chem. Soc.
1987,
109:
6844
3a Back TG.
Dyck BP.
Nan S.
Tetrahedron
1999,
55:
3191
3b Nishibayashi Y.
Srivastava SK.
Takada H.
Fukuzawa S.-I.
Uemura S.
J. Chem. Soc., Chem. Commun.
1995,
2321
3c Wirth T.
Angew. Chem., Int. Ed. Engl.
1995,
34:
1726
3d Fujita K.-I.
Iwaoka M.
Tomoda S.
Chem. Lett.
1992,
1123
4 Kang SH.
Kim M.
J. Am. Chem. Soc.
2003,
125:
4684
5a Hass J.
Piguel S.
Wirth T.
Org. Lett.
2002,
4:
297
5b Grossman RB.
Trupp RJ.
Can. J. Chem.
1998,
76:
1233
6a Grundon MF.
Stewart D.
Watts WE.
J. Chem. Soc., Chem. Commun.
1973,
573
6b Carlson RM.
Funk AH.
Tetrahedron Lett.
1971,
27:
3661
7 Kang SH.
Lee SB.
Park CM.
J. Am. Chem. Soc.
2003,
51:
15748
8a Mikami K.
Terada M.
Matsumoto Y.
Tanaka M.
Nakamura Y.
Micropor. Mesopor. Mater.
1998,
21:
461
8b Terada M.
Matsumoto Y.
Nakamura Y.
Mikami K.
J. Mol. Catal. A: Chem.
1998,
132:
165
8c Inoue T.
Kitagawa O.
Saito A.
Taguchi T.
J. Org. Chem.
1997,
62:
7384
8d Keck GE.
Krishnamurthy D.
J. Am. Chem. Soc.
1995,
117:
2363
8e Keck GE.
Tarbet KH.
Geraci LS.
J. Am. Chem. Soc.
1993,
115:
8467
9a Lingenfelter DS.
Helgeson RC.
Cram DJ.
J. Org. Chem.
1981,
46:
393
9b Hu Q.
Vitharana D.
Pu L.
Tetrahedron: Asymmetry
1995,
6:
2123
9c Qian C.
Huang T.
Zhu C.
Sun J.
J. Chem. Soc., Perkin Trans. 1
1998,
2097
9d Cram DJ.
Helgeson RC.
Peacook SC.
Kaplan LJ.
Domeier LA.
Moreau P.
Koga K.
Mayer JM.
Chao Y.
Siegel MG.
Hoffmann DH.
Sogah GDY.
J. Org. Chem.
1978,
43:
1930
10
General Procedure for the Asymmetric Iodocyclization. To a mixture of (R )-Binol (17 mg, 0.06 mmol) and 4Å molecular sieve (57 mg) in t -butyl methyl ether (3.5 mL) was added Ti(Oi -Pr)4 (17 mg, 0.06 mmol) in t -butyl methyl ether (0.7 mL) at r.t., and the resulting mixture was stirred at that temperature for 1.5 h. After cooling the generated (R )-Binol-Ti(IV) complex to 0 °C, the substrate 2 (57 mg, 0.3 mmol) in t -butyl methyl ether (1.5 mL) and N -iodo-succinimide (81 mg, 0.36 mmol) were added in sequence. The iodocyclization was allowed to proceed at 0 °C for 3 h, and then quenched with 10% aq Na2 S2 O3 (3 mL). The reaction mixture was extracted with Et2 O (3 × 5 mL), and subsequently the organic layer was filtered through celite. Evaporation of the volatile materials in vacuo followed by silica gel column chromatography (Et2 O-hexane = 1:15) yielded tetrahydrofuran 3 (89 mg, 93%).
