Theoretical studies of the effects of α-substituents on the resonance demand of 4-methoxybenzyl carbocations

✍ Scribed by Ikchoon Lee; Soo Chung Dong; Jin Jung Hak

• Publisher: Elsevier Science
• Year: 1994
• Tongue: French
• Weight: 393 KB
• Volume: 50
• Category: Article
• ISSN: 0040-4020
• DOI: 10.1016/s0040-4020(01)85283-2

✦ Synopsis

Our AM1 results show that : ( i ) Electron-withdrawing p&z effect of u -substitueuts leads to tbeamodynamic destabilization, B Al? > 0, of bensylic carimcations. (ii) The increments of positive charge on C. aud on metboxy-0 accompauying the csrbocation formation are linearly correlated with the electron witbdrawhrg polar effect, ff* ; the positive charge on G is more strongly forced away onto the oxygen of the 4-metboxy group by a greater electron withdrawing power of the a -substituent. Recently considerable attention of physical organic chemist has been dhected to reactions involving carbocation intemmdiates beariug elech-on withdraw substituents attached at the positive