THEORETICAL-STUDIES OF THE EFFECTS OF ALPHA-SUBSTITUENTS ON THE RESONANCE DEMAND OF 4-METHOXYBENZYL CARBOCATIONS

被引：12

作者：

LEE, I ^{[1
]}

CHUNG, DS ^{[1
]}

JUNG, HJ ^{[1
]}

机构：

[1] DONGSHIN UNIV,DEPT CHEM,CHOONGNAM 520714,SOUTH KOREA

来源：

TETRAHEDRON | 1994年 / 50卷 / 27期

关键词：

D O I：

10.1016/S0040-4020(01)85283-2

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

Our AM1 results show that : (i) Electron-withdrawing polar effect of alpha-substituents leads to thermodynamic destabilization, delta Delta H-0 > 0, of benzylic carbocations. (ii) The increments of positive charge on C-alpha and on methoxy-O accompanying the carbocation formation are linearly correlated with the electron withdrawing polar effect, sigma*; the positive charge on C-alpha is more strongly forced away onto the oxygen of the 4-methoxy group by a greater electron withdrawing power of the alpha-substituent.

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页码：7981 / 7986

页数：6

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