Directed manganation of functionalized arenes and heterocycles using tmp2Mn x 2 MgCl2 x 4 LiCl.
Directed manganation of functionalized arenes and heterocycles using tmp2Mn x 2 MgCl2 x 4 LiCl.
复制标题
使用 tmp2Mn x 2 MgCl2 x 4 LiCl 对官能化芳烃和杂环进行定向锰化
DOI：
10.1002/anie.200903505
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发表时间：
2009
影响因子：
--
通讯作者：
Knochel
中科院分区：
文献类型：
--
作者：
Wunderlich;Kienle;Knochel
芳烃和杂环的金属化是相当有意义的，因为它允许通过有机金属中间体的化学计量形成使未活化的C±H键直接官能化。鉴于不饱和有机底物的锂化已被广泛使用，[1]寻找与更多官能团相容并在接近室温下进行的金属化过程一直是相当努力的主题。在这方面，各种“ATE”碱的开发是非常有前途的。[2，3]此外，使用空间受阻的金属酰胺与LiCl络合，类型为tmpnM1·xM2Xm·yLiCl(tMP=2，2，6，6-四甲基哌啶；M1=镁，[4]锌，[5]铝；[6]M2=镁)已经导致了高度的化学和区域选择性的金属化。LiCl的存在是必不可少的，因为它增加了这些金属碱的溶解度，并通过降低它们的聚集状态来增强它们的动力学碱性。[7]由于过渡金属显示出主族元素无法获得的反应模式，因此制备过渡金属酰胺已被设想。[8]特别是锰，由于其价格低廉，毒性适中，反应活性多样，引起了人们的合成兴趣。[9]在此，我们报告了一种新的锰碱[10]，它显示出独特的化学选择性和反应性，允许有效地形成C？C和C？N键。此外，便利的金属化条件使其成为合成应用的非常实用的基础。因此，在08C下向MnCl2·2LiCl[11](1当量)中加入商业可得的tMMPMgCl.LiCl2(2；2.0当量)，然后在258℃下搅拌3h，在四氢呋喃中得到0.5m的锰酰胺3溶液(方案1)。碱基3具有极好的热稳定性，可以在258℃下储存8周以上，不会有明显的分解。初步实验立即表明，新的锰碱具有与镁碱2非常不同的反应活性。因此，尽管2与2-苯基-1，3，4-恶二唑(4)的反应只产生环裂解产物(PHCN和NCOMgCl)，但其
The metalation of arenes and heterocycles is of considerable interest, since it allows direct functionalization of an unactivated CÀH bond by the stoichiometric formation of an organometallic intermediate. Whereas the lithiation of unsaturated organic substrates has been extensively used,[1] the search for metalation procedures that are compatible with more functional groups and proceed at close to room temperature has been the subject of considerable efforts. In this regard, the development of various “ate” bases has been very promising.[2, 3] Also, the use of sterically hindered metallic amides complexed by LiCl of the type tmpnM1· xM2Xm· yLiCl (tmp= 2, 2, 6, 6-tetramethylpiperidyl; M1= Mg,[4] Zn,[5] Al;[6] M2= Mg) has led to highly chemoand regioselective metalations. The presence of LiCl was essential since it increases the solubility of these metallic bases and enhances their kinetic basicity by lowering their aggregation states.[7]The preparation of transition-metal amides has been envisioned, as transition metals display reactivity patterns not accessible for main-group elements.[8] Especially manganese, owing to its low price, moderate toxicity, and versatile reactivity, is of synthetic interest.[9] Herein, we report a new manganese base [10] that shows a unique chemoselectivity and reactivity, allowing the efficient formation of CÀC and CÀN bonds. Furthermore, the convenient metalation conditions make it a very practical base for synthetic applications. Thus, the addition of commercially available tmmpMgCl· LiCl (2; 2.0 equiv) to MnCl2· 2 LiCl [11](1 equiv) at 08C with subsequent stirring at 258C for 3 h provides the manganese amide 3 as a 0.5 m solution in THF (Scheme 1). The base 3 has an excellent thermal stability and can be stored at 258C for more than eight weeks without appreciable decomposition. Preliminary experiments show immediately that the new Mn base has a very different reactivity than the Mg base 2. Thus, whereas the reaction of 2 with 2-phenyl-1, 3, 4-oxadiazole (4) provides only ring fragmentation products (PhCN and NCOMgCl), its
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影响因子：
1.8
作者：
NEGISHI, E;BAGHERI, V;STOLL, AT
通讯作者：
STOLL, AT
影响因子：
5.2
作者：
Lin, Wenwei;Baron, Oliver;Knochel, Paul
通讯作者：
Knochel, Paul
钯催化酰基氯和有机锌化合物合成酮
影响因子：
3.6
作者：
R. Grey
通讯作者：
R. Grey
氨基铜酸盐和氨基铜酸锌氧化合成胺和肼的通用方法
DOI：
10.1055/s-1997-1218
发表时间：
1997
期刊：
Synthesis
影响因子：
--
作者：
F. Cane;D. Brancaleoni;P. Dembech;A. Ricci;G. Seconi
通讯作者：
G. Seconi
影响因子：
2.8
作者：
H. Shinokubo;K. Oshima
通讯作者：
H. Shinokubo;K. Oshima