Deprotonative Metalation of Substituted Benzenes and Heteroaromatics Using Amino/Alkyl Mixed Lithium-Zinc Combinations
作者:Katia Snégaroff、Shinsuke Komagawa、Floris Chevallier、Philippe C. Gros、Stéphane Golhen、Thierry Roisnel、Masanobu Uchiyama、Florence Mongin
DOI:10.1002/chem.201000543
日期:2010.7.19
Different homoleptic and heteroleptic lithium–zinc combinations were prepared, and structural elements obtained on the basis of NMR spectroscopic experiments and DFT calculations. In light of their ability to metalate anisole, pathways were proposed to justify the synergy observed for some mixtures. The best basic mixtures were obtained either by combining ZnCl2⋅TMEDA (TMEDA=N,N,N′,N′‐tetramethylethylenediamine)
制备了不同的均溶和异溶锂-锌组合,并根据NMR光谱实验和DFT计算获得了结构元素。考虑到它们使苯甲醚金属化的能力,提出了一些途径以证明对某些混合物观察到的协同作用是正确的。通过结合ZnCl 2 · TMEDA(TMEDA = N,N,N',N'-四甲基乙二胺)([tmp = 2,2,6,6-四甲基哌啶子基; 3当量)或通过用烷基取代先有混合物中的tmp之一。接下来研究了据推测形成的芳香族锌酸锂的反应性,并证明其与底物,碱和亲电试剂有关。芳族锌酸锂最终参与了钯与芳族氯化物和溴化物的交叉偶联反应。