THE ALDOL REACTION FOR 2,3-ETA-2-FURAN COMPLEXES OF OSMIUM(II) - CYCLIZATION ACROSS C(2) AND C(4) TO FORM A NEW HETEROCYCLE

被引：18

作者：

LIU, RG ^{[1
]}

CHEN, HY ^{[1
]}

HARMAN, WD ^{[1
]}

机构：

[1] UNIV VIRGINIA,DEPT CHEM,CHARLOTTESVILLE,VA 22901

来源：

ORGANOMETALLICS | 1995年 / 14卷 / 06期

关键词：

D O I：

10.1021/om00006a035

中图分类号：

O61 [无机化学];

学科分类号：

070301 ; 081704 ;

摘要：

The pentaammineosmium(II) complex of 5-methylfuran (2) undergoes stereoselective aldol reactions with various aldehydes in the presence of a Lewis acid (Sn(OTf)(2) or BF3.OEt(2)) to give 4-acetylated-4,5-dihydrofuran complexes where the aldehyde carbonyl group has been incorporated into the dihydrofuran nucleus, A detailed analysis of the substitution pattern and stereochemistry of these products reveals a reaction sequence involving an aldol reaction at C(4) of the eta(2)-furan followed by nucleophilic displacement at C(2) of the furan oxygen by the aldol-derived alkoxide. When the parent furan complex is subjected to otherwise identical reaction conditions, this rearrangement does not occur, Instead, two diastereomers of a novel bicyclic diacetal are formed.

引用

页码：2861 / 2867

页数：7

共 15 条

[1]

Bard A. J., 2001, ELECTROCHEMICAL METH, V2nd, P50

[2] LIGHT-CATALYZED ORGANIC REACTIONS .1. THE REACTION OF CARBONYL COMPOUNDS WITH 2-METHYL-2-BUTENE IN THE PRESENCE OF ULTRAVIOLET LIGHT [J].