High regio-, chemo-, and stereoselectivity via low-temperature 4+3 cycloadditions.: Convergent synthesis of multifunctionalized vinylmetals (M = Si, Sn) and S-vinyl benzenecarbothioates

被引：38

作者：

Beck, H ^{[1
]}

Stark, CBW ^{[1
]}

Hoffmann, HMR ^{[1
]}

机构：

[1] Univ Hannover, Dept Organ Chem, D-30167 Hannover, Germany

来源：

ORGANIC LETTERS | 2000年 / 2卷 / 07期

关键词：

D O I：

10.1021/ol991386p

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

[GRAPHICS] A series of enantiomerically pure 8-oxabicyclo[3.2.1]oct-6-en-3-ones functionalized in the unsaturated two-carbon bridge has been prepared by the title reaction. Carbocation reactivity has been fined-tuned at -95 degrees C and adjusted to diene nucleophilicity. Conventional electrophilic substitution of 3-silylated and 3-stannylated furan is suppressed in favor of the rapid 4 + 3 cycloaddition mode. In the case of cycloadduct 13A, stereoselectivity (17:1) is perfectly matched to regioselectivity (17:1). High stereoselection as well as unprecedented regioselection and chemoselection is attributed to the low-temperature cycloaddition protocol and the design of chiral auxiliary and tether.

引用

页码：883 / 886

页数：4

共 39 条

[1] Synthesis of polysubstituted 3-thiofurans by regiospecific mono-ipso-substitution and ortho-metallation from 3,4-dibromofuran [J].

AlvarezIbarra, C ;

Quiroga, ML ;

Toledano, E .

TETRAHEDRON, 1996, 52 (11) :4065-4078

[2]

[Anonymous], 1997, Organic Reactions

[3]

Beck H, 1999, EUR J ORG CHEM, V1999, P2991

[4] A very rapid stereocontrolled entry to highly functionalized [5-8-5] ring systems using the Saegusa reaction [J].

Blake, AJ ;

Highton, AJ ;

Majid, TN ;

Simpkins, NS .

ORGANIC LETTERS, 1999, 1 (11) :1787-1789

[5]

CHIU P, 1997, TOP CURR CHEM, V190, P3

[6] Synthesis of the C29-C37 segment of spongistatin 1 [J].

Dunkel, R ;

Treu, J ;

Hoffmann, HMR .

TETRAHEDRON-ASYMMETRY, 1999, 10 (08) :1539-1549

[7] Asymmetric synthesis of polyacetate derived building blocks with α-oxyanion functionality.: Lewis acid catalyzed opening of 2,9-dioxabicyclo[3.3.1]nonan-3-ones [J].

Dunkel, R ;

Hoffmann, HMR .

TETRAHEDRON, 1999, 55 (28) :8385-8396

[8] 8-Oxabicyclo[3.2.1]oct-6-en-3-one as a module for the synthesis of beta-alkoxy-delta-valerolactones relevant to natural products and drugs [J].

Dunkel, R ;

Mentzel, M ;

Hoffmann, HMR .

TETRAHEDRON, 1997, 53 (44) :14929-14936

[9]

Gaertzen O, 1999, SYNLETT, P1041

[10] Synthesis of enantiopure C-glycosides and pseudo C-glycosides:: Lewis-acid mediated heterolysis of methyl acetals [J].

Gaertzen, O ;

Misske, AM ;

Wolbers, P ;

Hoffmann, HMR .

TETRAHEDRON LETTERS, 1999, 40 (35) :6359-6363

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