24小时热门版块排行榜    

查看: 1253  |  回复: 2

lwn_2010

银虫 (正式写手)

[求助] MnCl2催化偶联KUMADA反应

我采用MnCl2催化合成沙坦联苯,催化剂的水分已除干净,溶剂THF水分含量已达指标,但却反应很不好,我想求助一下影响MnCl2催化的还有那些因素
回复此楼

» 猜你喜欢

» 本主题相关价值贴推荐,对您同样有帮助:

Ilikeyou
已阅   回复此楼   关注TA 给TA发消息 送TA红花 TA的回帖

conlinkl

木虫 (正式写手)

【答案】应助回帖

The Kumada cross-coupling, also known as the Kumada-Corriu reaction, is a nickel catalyzed reaction between a Grignard reagent and an aryl halide. This organometallic reaction is very useful for C-C bond formation. It also works for alkyl and vinyl halides and in some cases, palladium catalysts can be used instead of nickel.

Read more: How to Do a Kumada Coupling | eHow.com http://www.ehow.com/how_6014768_ ... .html#ixzz1mY4CWp5w
1
Place your aryl halide (1 equivalent) in a dry reaction flask under an inert atmosphere such as nitrogen or argon. Add anhydrous diethyl ether and degas the solution by freeze-pump-thaw cycles or by bubbling with argon or nitrogen.

2
Next, you need to add your catalyst (typically 1-10 mol%) to the degassed reaction mixture as a solid. The catalyst is most often Ni(dppe)Cl2 (CAS: 14647-23-5), Ni(dppp)Cl2 (CAS: 15629-92-2) or Ni(dppf)Cl2 (CAS: 67292-34-6) but various other nickel and palladium catalysts have also been used widely.

3
From an addition funnel, you should now add a solution of your Grignard reagent (a slight excess, either freshly prepared or from a commercial source) to the reaction mixture and subsequently warm the reaction mixture to gentle reflux. The reaction will typically go to completion with reflux over night.

4
Workup typically consists of an aqueous wash followed by column chromatography and recrystallization to afford your desired product.



Read more: How to Do a Kumada Coupling | eHow.com http://www.ehow.com/how_6014768_ ... .html#ixzz1mY46yNzO
人生为棋我愿为卒,虽步履缓慢可谁曾见我后退一步
2楼2012-11-07 20:56:44
已阅   回复此楼   关注TA 给TA发消息 送TA红花 TA的回帖

心身一体

金虫 (著名写手)

菜芽

师兄你好,我是研一的有机化学的学生! 不知道您做的 MnCl2催化的Kumada反应后面做的怎么样啦? 学弟我现在做这个也遇到问题了,,,收率较低,,,而且老师还要求不要让格式试剂过量,还请师兄指点密经!不知道有没有相关文献? 我一直没有搜索到!

[ 发自手机版 http://muchong.com/3g ]
君欲善其事必先利其器善,始善终。珍惜,态度,责任。。
3楼2016-03-06 17:19:16
已阅   回复此楼   关注TA 给TA发消息 送TA红花 TA的回帖
相关版块跳转 我要订阅楼主 lwn_2010 的主题更新
最具人气热帖推荐 [查看全部] 作者 回/看 最后发表
[基金申请] 确定了,国自然21号放榜 +4 布布和一二 2026-08-10 4/200 2026-08-10 17:48 by ZJTJZ
[基金申请] 静等基金结果 +5 gjjjzhong 2026-08-10 16/800 2026-08-10 17:19 by Tide man
[基金申请] 关于Filecode分析方法 +3 majunge000 2026-08-10 3/150 2026-08-10 15:46 by lch2012
[基金申请] 8月时间戳变的,举个手。玩一下,释放压力 +11 archvillain 2026-08-04 13/650 2026-08-10 14:41 by seekfind
[基金申请] 综述论文作为代表作会不会影响评审专家的印象分? +10 yufeiwaner 2026-08-09 10/500 2026-08-10 13:44 by cdutwml
[基金申请] 关于代码变化问题,想知道的进来 +16 且听虎啸 2026-08-07 23/1150 2026-08-10 12:35 by majunge000
[基金申请] 这样的filecode谁见过 +11 布布和一二 2026-08-08 22/1100 2026-08-10 11:10 by wmfsnow
[基金申请] filecode与中标关系的预测 +5 布布和一二 2026-08-07 5/250 2026-08-09 16:15 by 袁向阳007
[基金申请] fileCode有新解读? +10 Tide man 2026-08-08 18/900 2026-08-09 12:55 by 仁砚薪传
[基金申请] 关于豆爷回答的JTJC与%2F数量 +5 yang182083 2026-08-06 7/350 2026-08-08 18:29 by zhanghaozhu
[基金申请] 国基金的申报应该改成非等额制,评价高的钱多评价低的钱少,但是增加资助率 +7 a089 2026-08-07 7/350 2026-08-08 18:05 by gltch
[基金申请] 基金中了 +14 laoda193707 2026-08-06 14/700 2026-08-08 00:23 by 实验小白ha
[基金申请] 关于filecode +4 布布和一二 2026-08-07 7/350 2026-08-07 22:55 by zhanghaozhu
[基金申请] 娱乐 +6 Tide man 2026-08-03 6/300 2026-08-07 22:40 by 铁帽子农民
[基金申请] 化学口download_prp&fileCode的固定段好像这几天一直没变,有变的大神么? +3 Tide man 2026-08-07 4/200 2026-08-07 22:39 by Tide man
[基金申请] 听说今天filecode变了 +24 布布和一二 2026-08-06 47/2350 2026-08-07 16:02 by zhiyanjiang
[基金申请] filecode +14 等待解的谜 2026-08-06 19/950 2026-08-07 12:20 by wlwhappy
[基金申请] filecode +8 布布和一二 2026-08-06 11/550 2026-08-06 20:41 by tangpu318
[基金申请] 有没有H口的?有收到消息的吗? +3 超级海虾 2026-08-04 3/150 2026-08-04 17:26 by 学教育滴
[基金申请] 纯娱乐,不喜欢勿喷 +7 Tide man 2026-08-04 10/500 2026-08-04 15:10 by loufangrui
信息提示
请填处理意见