Mixed aggregates of lithium tetramethylpiperidide with butyllithium: Stereoselectivity of ketone enolization

被引：28

作者：

Balamraju, Y ^{[1
]}

Sharp, CD ^{[1
]}

Gammill, W ^{[1
]}

Manuel, N ^{[1
]}

Pratt, LM ^{[1
]}

机构：

[1] Louisiana Tech Univ, Dept Chem, Ruston, LA 71272 USA

来源：

TETRAHEDRON | 1998年 / 54卷 / 26期

关键词：

D O I：

10.1016/S0040-4020(98)00402-5

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

The enolization stereoselectivity of 3-pentanone by lithium tetramethylpiperidide mixed aggregates with butyllithium was studied and the results were compared to those obtained using lithium tetramethylpiperidide alone. The mixed aggregate resulted in a slightly higher stereoselectivity, and the selectivity increased with decreasing percent conversion of the lithium base. Ab initio and semiempirical PM3 calculations were performed to determine the activation enthalpies for the enolization reactions and the calculations were compared to the experimental results. (C) 1998 Elsevier Science Ltd. All rights reserved.

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页码：7357 / 7366

页数：10

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