20. The energy of the trans conformation of the anion is 7.57 kJ/mol lower than the cis conformation, and the energy barrier of the conformation invert is only 3.05 kJ/mol. It shows the conformation invert reaction is controlled by thermodynamics and will happen easily. The result can explain the epimerization of 2-benzyl-2-ethoxycarbonyl-cyclopentanol in Williamson ether synthesis.
其中，醛基與酯羰基形成的反式構(gòu)象的負(fù)離子能量比順式構(gòu)象的負(fù)離子能量低7.57 kJ/mol，而構(gòu)象翻轉(zhuǎn)的活化能僅為3.05 kJ/mol，說明構(gòu)象翻轉(zhuǎn)為熱力學(xué)控制的反應(yīng)，順式構(gòu)象即能夠自發(fā)翻轉(zhuǎn)呈反式構(gòu)象，解釋了在Williamson醚合成反應(yīng)中順、反構(gòu)型翻轉(zhuǎn)的現(xiàn)象。
invert 詞典解釋
1. 使反向;使倒置
If you invert something, you turn it the other way up or back to front.
e.g. Invert the cake onto a cooling rack.
把蛋糕倒扣在冷卻架上。
e.g. ...a black inverted triangle.
一個黑色的倒三角
2. 使顛倒
If you invert something, you change it to its opposite.
e.g. They may be hoping to invert the presumption that a defendant is innocent until proved guilty.
他們可能有望顛覆“被告在證實有罪之前是無辜的”這一假設(shè)。
e.g. ...a telling illustration of inverted moral values.
是非顛倒的道德觀的有力證明
invert 單語例句
1. Place chabei upside down over wen xiang bei and invert the two without allowing any tea to escape.
invert 英英釋義
verb
1. invert
1. turn inside out or upside down
Synonym: turn back reverse
2. invert
2. reverse the position, order, relation, or condition of
e.g. when forming a question, invert the subject and the verb
Synonym: reverse
3. make an inversion (in a musical composition)
e.g. here the theme is inverted
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