作者chicyupin (zzzZZZ)
看板Chemistry
标题[问题]还原力:LiAlH4 >NaBH4 的原因?
时间Fri Apr 11 22:10:51 2008
如题...
请问一下这个小小的问题
不知道这两个还原剂之间还原力的差别
主要原因是什麽??
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※ 发信站: 批踢踢实业坊(ptt.cc)
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1F：推 buteo:H与B.Al的电负度差应该是主因 (hydride带的部份负电多寡) 04/11 22:21
2F：→ buteo:可参考2347篇 04/11 22:23
3F：→ chicyupin:嗯 感谢^^ XDDDDDDDDD 04/11 22:35
4F：推 volley:but i do not think the hard-soft consideration could 04/11 22:58
5F：→ volley:explain why LiAlH4 behaves reductant but NaH behaves 04/11 22:59
6F：→ volley:strong base! i think the electronegativity indeed can 04/11 23:00
7F：→ volley:give good explaination about the difference between 04/11 23:01
8F：→ volley:LiAlH4 and NaBH4. 04/11 23:02
9F：→ volley:LiAlH4, which is almost the strongest reductant, is 04/11 23:02
10F：→ volley:due to the coordination of aluminum atom onto reducible 04/11 23:04
11F：→ volley:functional group. then hydride is induced to attack 04/11 23:05
12F：→ volley:that functional group. 04/11 23:05
13F：→ volley:NaH can not form such complex with reducible functional 04/11 23:06
14F：→ volley:groups, thus that hydride can not be a reductant! 04/11 23:07
15F：推 buteo:学长你就打篇文章让我M一下嘛 ^^ 04/11 23:21
16F：推 jessti:Al-H键共价性比Na-H强的多 半径差异 04/11 23:54
17F：→ chicyupin:So the complex means? 04/12 01:19
18F：推 jessti:Al有能力当lewis acid跟反应物产生complex 增加反应位置的 04/12 03:08
19F：→ jessti:部分正电 让hydride好攻击 04/12 03:10
20F：→ chicyupin:所以"主要"的原因是因为产生complex,并非电负度差异罗? 04/12 13:58
21F：→ chicyupin:还有那产生的complex是以什麽型态存在? 结构如何? 04/12 13:59
22F：→ chicyupin:可以麻烦解释一下吗? 因为我都查不到相关的资料> < 04/12 13:59
23F：→ chicyupin:只查到下列网址的部份解释 但我看不大懂所指 04/12 14:01