Abstract
In the presence of catalytic amounts of PtCl2 and AgX (X = OTf or SbF6 ), (Z )-6-trimethylsilyl-5-hexen-1-ol and (Z )-5-trimethylsilyl-4-penten-1-ol reacted smoothly with aldehydes to give 2,3-disubstituted tetrahydropyrans and tetrahydrofurans, respectively, in good to high yields. The reaction mechanism involves the isomerization of the starting vinylsilanes to the corresponding allylsilanes and subsequence Prins-type annulation with aldehydes.
Key words
aldehydes - annulations - catalysis - silicon - tandem reactions
References
1 Snider BB. In
Comprehensive Organic Synthesis
Vol. 2:
Trost BM.
Fleming I.
Pergamon Press;
Oxford:
1991.
Chap. 2.1.
p.527
2a Stapp PR.
J. Org. Chem.
1969,
34:
479
2b Loh T.-P.
Hu Q.-Y.
Tan K.-T.
Cheng H.-S.
Org. Lett.
2001,
3:
2669
3a Mohr P.
Tetrahedron Lett.
1993,
34:
6251
3b Mohr P.
Tetrahedron Lett.
1995,
36:
2453
3c Sano T.
Oriyama T.
Synlett
1997,
716
3d Suginome M.
Iwanami T.
Ito Y.
Chem. Commun.
1999,
2537
3e Suginome M.
Iwanami T.
Yamamoto A.
Ito Y.
Synlett
2001,
1042
3f Kjellgren J.
Szabo KJ.
Tetrahedron Lett.
2002,
43:
1123
3g Sarkar TK.
Haque SA.
Basak A.
Angew. Chem. Int. Ed.
2004,
43:
1417
4a Mekhalfia A.
Markó IE.
Adams H.
Tetrahedron Lett.
1991,
32:
4783
4b Markó IE.
Mekhalfia A.
Tetrahedron Lett.
1992,
33:
1799
4c Markó IE.
Bayston DJ.
Tetrahedron Lett.
1993,
34:
6595
4d Markó IE.
Plancher J.-M.
Tetrahedron Lett.
1999,
40:
5259
4e Kopecky DJ.
Rychnovsky SD.
J. Am. Chem. Soc.
2001,
123:
8420
5a Miura K.
Hondo T.
Okajima S.
Nakagawa T.
Takahashi T.
Hosomi A.
J. Org. Chem.
2002,
67:
6082
5b Miura K.
Hosomi A.
Synlett
2003,
143 ; and references therein
6a Seki Y.
Takeshita K.
Kawamoto K.
Murai S.
Sonoda N.
J. Org. Chem.
1986,
51:
3890
6b Jun C.-H.
Crabtree RH.
J. Organomet. Chem.
1993,
447:
177
6c Doyle MP.
High KG.
Nesloney CL.
Clayton TW.
Lin J.
Organometallics
1991,
10:
1225
7a Harrod JF.
Chalk AJ.
J. Am. Chem. Soc.
1964,
86:
1776
7b Cramer R.
Lindsey RV.
J. Am. Chem. Soc.
1966,
88:
3534
8a Kündig EP.
Saudan CM. In
Lewis Acids in Organic Synthesis
Vol. 2:
Yamamoto H.
Wiley-VCH;
Weinheim:
2000.
p.597
8b Fujimura O.
J. Am. Chem. Soc.
1998,
120:
10032
8c Nishibayashi Y.
Yoshikawa M.
Inada Y.
Milton MD.
Hidai M.
Uemura S.
Angew. Chem. Int. Ed.
2003,
42:
2681
9 As a preliminary result, we found that the PtCl2 -catalyzed (5 mol%) reaction of 2 with 3e gave 4e (45 °C, 24 h, 24% yield) although the conditions were not optimized.
10 For the origin of stereoselective formation of trans -4 and cis -8 , see ref. 3b,f and ref. 3a, respectively.
11 Z )-1 and (Z )-7 can easily be prepared from 4-pentyn-1-ol and 5-hexyn-1-ol, respectively, which are commercially available. See: Miura K.
Okajima S.
Hondo T.
Nakagawa T.
Takahashi T.
Hosomi A.
J. Am. Chem. Soc.
2000,
122:
11348
12 Overman LE.
Angew. Chem.
1984,
96:
565
2 (L)-AgOTf catalyst system:
13a Kataoka Y.
Matsumoto O.
Tani K.
Organometallics
1996,
15:
5246
13b Liu C.
Han X.
Wang X.
Widenhoefer RA.
J. Am. Chem. Soc.
2004,
126:
3700
13c Oyamada J.
Kitamura T.
Tetrahedron Lett.
2005,
46:
3823
