ARENE-METAL COMPLEXES .13. REACTION OF SUBSTITUTED (BENZENE)TRICARBONYLCHROMIUM COMPLEXES WITH NORMAL-BUTYLLITHIUM
ARENE-METAL COMPLEXES .13. REACTION OF SUBSTITUTED (BENZENE)TRICARBONYLCHROMIUM COMPLEXES WITH NORMAL-BUTYLLITHIUM
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DOI：
10.1021/jo01301a002
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发表时间：
1980-01-01
影响因子：
3.6
通讯作者：
TRAHANOVSKY, WS
中科院分区：
文献类型：
--
作者：
CARD, RJ;TRAHANOVSKY, WS
研究了一系列取代苯三羰基铬配合物与正丁基锂的反应。该反应似乎通过质子提取进行，产生（芳基锂）三羰基铬中间体，然后可以通过加入伯烷基卤化物（通常是甲基碘）淬灭。可以获得新的烷基化络合物，或者可以将材料解络合以产生烷基化苯衍生物。以这种方式，（单烷基苯）三羰基铬络合物主要产生间二烷基苯;（氟苯）三羰基铬产生邻氟甲苯;（苯甲醚）三羰基铬主要产生2，6-二甲基苯甲醚;并且（N，N-二甲基苯胺）三羰基铬产生几种异构的N，N-二甲基甲苯胺。（碘苯）三羰基铬与正丁基锂进行金属-卤素交换，并可根据反应条件转化为甲苯或正丁基苯。与已知的化学的未络合的类似物的比较demonstrsthe强烈的激活效果的tricarbonylchromium部分对这些反应。特别有趣的是，在这些条件下，（氟苯）三羰基铬与正丁基锂的反应是质子夺取而不是净亲核置换，如使用碱性较低的亲核试剂时所观察到的那样。由于其易于添加到芳香核和从芳香核移除，三羰基铬基团似乎是暂时改变芳香体系的反应性的非常有吸引力的手段。最近，出现了对这一领域工作的若干评论。2
Reaction of a series of substituted (benzene) tricarbonylchromiumcomplexes with n-butyllithium has been examined. The reaction appears to proceed via proton abstraction to yield an (aryllithium) tricarbonylchromium intermediate which may then be quenched by the addition of primary alkyl halides, usually methyl iodide. New, alkylated complexes may be obtained, or the material may be decomplexed to yield alkylated benzene derivatives. In this manner,(monoalkylbenzene) tricarbonylchromium complexes yield mainly m-dialkylbenzenes;(fluorobenzeneRricarbonylchromium yields o-fluorotoluene;(anisole) tricarbonylchromium yields mainly 2, 6-dimethylanisole; and (N,/V-dimethylaniline) tricarbonylchromium yields several isomeric N, N-dimethyltoluidines.(Iodobenzene) tricarbonylchromium undergoes metal-halogen exchange with n-butyllithium and may be converted to either toluene or n-butylbenzene depending on the reaction conditions. Comparison with known chemistry of the uncomplexed analogues demonstratesthe strongly activating effect of the tricarbonylchromium moiety on these reactions. It is especially interesting that under these conditions reaction of (fluorobenzene) tricarbonylchromium with n-butyllithium results in proton abstraction rather than net nucleophilic displacement, as observed when less basic nucleophiles are used.Reaction of substituted benzene-transition-metal com-plexes with nucleophiles and bases has received considerable attention over the past two decades. Because of the ease of its addition to and removal from the aromatic nucleus, the tricarbonylchromium group appears to be a very attractive means of temporarily altering the reactivity of aromatic systems. Recently, several reviews of work in this area have appeared. 2