Tetrahedron

Substituent effects on the SmI 2/Pd (0)-promoted carbohydrate ring-contraction of 5-alkynylpyranosides

JM Aurrecoechea, JH Gil, B López

文献索引：Aurrecoechea, Jose M.; Gil, Jesus H.; Lopez, Beatriz Tetrahedron, 2003 , vol. 59, # 36 p. 7111 - 7121

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被引用次数: 12

摘要

The effect of substituents on the reactivity and stereoselectivity of the SmI2/Pd (0)-promoted ring-contraction of 5-alkynylpyranosides has been examined using substrates substituted only at selected positions. While formation of 2-ethynylcyclopentanols takes place efficiently, an internal alkyne did not afford the expected product. The presence of peripheral alkoxy substituents leads to variable stereoselectivities that depend on the number and ...