Lithium Organozincate Complexes LiRZnX<sub>2</sub>: Common Species in Organozinc Chemistry
作者:Julia E. Fleckenstein、Konrad Koszinowski
DOI:10.1021/om200637s
日期:2011.9.26
the formation of lithium organozincates Li+RZnX2–. As the most common syntheses of RZnX reagents involve stoichiometric amounts of LiX salts, Li+RZnX2– complexes are supposedly widespread and may hold the key to understanding the marked effects of LiCl on the reactivity of organozinc halides. In contrast, we find Bu2Zn to have a much lower tendency to add LiCl and form ate complexes. This result is
我们结合电喷雾电离(ESI)质谱,电导率测量和NMR光谱研究了LiCl对有机锌卤化物RZnX(R = Bu,Bn,Ph; X =卤素)和二丁基锌Bu 2溶液的影响四氢呋喃中的锌。在RZnX,添加的LiX的情况下(X = Cl)的引线到RZnX的ESI信号强度的急剧上升2 - organozincate阴离子。同时,电导率大大提高,BuZnX的α-H原子的NMR吸收向高场移动。这些结果一致地表明形成了有机锌锂Li + RZnX 2 –。作为RZnX试剂中最常见的合成涉及化学计算量的LiX盐,锂+ RZnX 2 -复合物是所谓广泛,可以按住关键是理解上的有机锌卤化物的反应氯化锂的显着的效果。相反,我们发现Bu 2 Zn添加LiCl并形成配合物的趋势要低得多。该结果与文献中报道的LiCl对二有机锌化合物的反应性的弱作用相符。