IODOALKOXYLATION OF 1,5-ANHYDRO-2-DEOXY-HEX-1-ENITOLS (GLYCALS)

被引：59

作者：

HORTON, D

PRIEBE, W

SZNAIDMAN, M

机构：

[1] Department of Chemistry, The Ohio State University, Columbus

来源：

CARBOHYDRATE RESEARCH | 1990年 / 205卷

关键词：

D O I：

10.1016/0008-6215(90)80129-Q

中图分类号：

Q5 [生物化学]; Q7 [分子生物学];

学科分类号：

071010 ; 081704 ;

摘要：

Exclusive trans-addition is observed in the iodoalkoxylation of the 6-membered cyclic enol ethers 3,4-di-O-acetyl-l-rhamnal (1), 3,4-di-O-acetyl-l-fucal (2), and related glycal derivatives. The main products from 1 and from 3,4,6-tri-O-acetyl-d-glucal (3) thus had the α-manno configuration. Similarly, α-talo products were obtained from 2 in 87-93% yield. The product distribution is not affected by the electronegativity of the 5-substituent. It is concluded that steric factors in the glycal and the nucleophile affect only the step of trans-diaxial opening of the intermediate iodonium ion. Enhanced yields of the desired trans-diaxial products were observed in reactions of glycals having the lyxo configuration when the reactions were conducted in tetrahydrofuran or methanol. © 1990.

引用

页码：71 / 86

页数：16

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