Chauchau asked in 科學及數學化學 · 9 years ago

AL organic chem

圖片參考:http://imgcld.yimg.com/8/n/HA06578099/o/7012012900...

圖片參考:http://imgcld.yimg.com/8/n/HA06578099/o/7012012900...

why the underlined part does not undergo similar reaction with sodium ion?

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  • 9 years ago
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    sorry 只修讀中文,所以用中文回答 請見諒

    從酸鹼角度

    CH3CH2OH-->CH3CH2O- + H+

    C6H5OH->C6H5O^ + H+

    CH3CH2OH基本上不當作中性,因為解離度很低

    而C6H5OH 是酸性 且具腐蝕性

    所以從穩定性角度來看,CH3CH2O-是極不穩定,所以CH3CH2OH不會解離H+

    而C6H5O^-就穩定得多,所以C6H5OH 能離解一定量H+這題是考leaving group 也就是說明leaving group 穩定性

    所以從反應機理來看, I-攻擊缺電子碳中心,而離去基團

    離去基CH3C6H5CH2O-很不穩定(因為它和CH3CH2O-是同類) 也就不易離去

    而-OC6H5CH2OCH3相對地穩定(和C6H5O-是同類 ) 也就相對容易離去

    所以I-自然就會攻擊左邊和碳而離去-OC6H5CH2OCH3

    2012-02-04 11:25:54 補充:

    CH3CH2OH基本上當作中性,因為解離度很低

    Source(s): my
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