问题：关于LDA
类型：求助 (悬赏分:3分)
提问：yesu
等级：▲
版块：有机化学问题(jimuwei,fpcwin1211,netpanda,yjgzfl,Ftian,)
信誉：100%
回复：10
阅读：3144
时间：2006-03-07 13:24:44 编辑加入/取消收藏订制/取消短消息举报该贴

LDA的合成一般都是正丁基锂和二异丙胺反应

可听说可由锂和二异丙胺直接反应,请大侠指点

回复人：upstart,★ (药物设计及合成,感兴趣精细化工) 时间：2006-03-07 13:34:58 编辑	1楼
锂和氨在一起会发生Birch Reaction.不知锂和二异丙胺会发生什么.

回复人：tangyyer,★★★★★ (有空来逛逛my blog: http://tangyyer.blog.hexun.com) 时间：2006-03-07 14:00:56 编辑

2楼

一般的制法是：在-78℃,将20ml无水THF,1.05ml二异丙胺加入充满氮气的四颈瓶中,搅拌5min.将7.6mmol丁基锂缓慢加入四颈瓶中,历时大约40min。反应完毕后, 密封备用。用甲基锂代替丁基锂也可以。

(a) Preparation of phenyllithium. The procedure followed is essentially that of Gilman,
et al. (14) except that lithium sand instead of pieces of the metal was allowed to react with
the bromobenzene, using diethyl ether as a solvent. A 5-ml. portion of the reagent was
standardized with 0.1 N hydrochloric acid after being hydrolyzed with water (15). A Gilman
test (16) for the Grignard reagent was also performed on a 1 4 . sample.
To 500 ml. of a 1 molar solution of
phenyllithium contained in a 1000-ml. round-bottomed flask equipped with a mercury
(b) Preparation of disubstituted lithium amides.
COiKDENSATIONS EFFECTED BY THE ALKALI AMIDES. IV 167
sealed stirrer, a reflux condenser, and an addition funnel was added 0.5 mole of the appropriate
secondary amine listed in Table 111, at such a rate as to keep the ether gently
refluxing. The solution was stirred for five minutes after the addition of the amine was
completed and a 1-ml. sample was withdrawn and a Gilman test (16) made. If the test
was negative, the solution of the lithium disubstituted amide was ready for use. The conversion
of the amine to the corresponding lithium derivative was assumed to be quantitative.

回复人：moon,▲▲ () 时间：2006-03-07 16:23:43 编辑	3楼
闻所未闻

回复人：fuhonge,▲ () 时间：2006-03-07 20:10:07 编辑	4楼
金属锂可以直接和二异丙胺反应制备LDA，具体反应条件可参看“organic reagent"的”reduction and oxidation reagent"

回复人：maurice,★★ (自信,乐观,富于激情,积极面对人生) 时间：2006-03-07 21:55:27 编辑	5楼
金属锂可以直接和二异丙胺反应制备LDA,但是收率和质量都要低于正丁基锂!

回复人：readpen,▲ (相信自己相信明天) 时间：2006-03-07 22:42:07 编辑	6楼
收率太低

回复人：yesu,▲ (christ) 时间：2006-03-13 14:22:08 编辑	7楼
已经打分了。

回复人：sukaiyuan,▲ (将战斗进行到底！) 时间：2006-09-22 09:29:24 编辑	8楼
本人销售进口的正丁基锂，钢瓶包装，一般情况下为2.5mol/L，正己烷溶液，其他溶剂和浓度可以接受订货，工业化的可接受整柜集装箱订货。其他如仲丁基锂，叔丁基锂，LDA，氨基锂等也可接受订货。本人可以提供正丁基锂的详细检测方法和安全使用方法。 MOBILE: 13951781945，袁 EMAIL:sukaiyuan#126.com

回复人：thinkhot,▲ (化工在读生!) 时间：2006-09-27 14:08:17 编辑	9楼
这东西稳定性怎么样？

回复人：tff938,▲ (菜鸟) 时间：2008-01-04 15:52:55 编辑	10楼
进口的,加了稳定剂,不知道是什么东东,哪位知道在有机中可以作稳定剂的

得分人：tangyyer-1,fuhonge-1,

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