Deprotonative Metalation of Functionalized Aromatics Using Mixed Lithium-Cadmium, Lithium-Indium, and Lithium-Zinc Species
作者:Katia Snégaroff、Jean-Martial L'Helgoual'ch、Ghenia Bentabed-Ababsa、Tan Tai Nguyen、Floris Chevallier、Mitsuhiro Yonehara、Masanobu Uchiyama、Aïcha Derdour、Florence Mongin
DOI:10.1002/chem.200901432
日期:2009.10.5
N′‐tetramethylethylenediamine) or InCl3 (0.33 equiv) with [Li(tmp)] (tmp=2,2,6,6‐tetramethylpiperidino; 1.5 or 1.3 equiv, respectively) were compared with the previously described mixture of ZnCl2⋅TMEDA (0.5 equiv) and [Li(tmp)] (1.5 equiv) for their ability to deprotonate anisole, benzothiazole, and pyrimidine. [(tmp)3CdLi] proved to be the best base when used in tetrahydrofuran at room temperature, as demonstrated
在CDCl原位混合物2 ⋅TMEDA;(0.5当量TMEDA = Ñ,Ñ,N' ,N'四甲基乙二胺)或的InCl 3与[李(TMP)](TMP = 2,2,6,6(0.33当量) -tetramethylpiperidino;分别为1.5或1.3当量,)与氯化锌的前述混合物进行了比较2 ⋅TMEDA(0.5当量),用于他们的能力去质子苯甲醚,苯并噻唑,和嘧啶和[李(TMP)](1.5当量)。[(tmp)3当在室温下用于四氢呋喃中时,CdLi]被证明是最好的碱,随后用碘进行捕集证明了这一点。然后证明了Cd-Li碱适用于多种芳族化合物的金属化,包括带有反应性官能团的苯(CONEt 2,CO 2 Me,CN,COPh)或重卤素(Br,I)和杂环(来自呋喃) ,噻吩,吡咯,恶唑,噻唑,吡啶和二嗪系列)。得益于双重激活位置的五元杂环在室温下也被双去质子化。由此获得的芳族碳酸钙可参与钯催化的交叉偶联反应,或简单地用酰氯淬灭。