Department of Chemistry, Texas A&M University, College Station, Texas 77842, United States.
J Am Chem Soc. 2022 Sep 14;144(36):16631-16637. doi: 10.1021/jacs.2c07207. Epub 2022 Aug 29.
A long-standing problem in the area of organolithium chemistry has been the need for a highly reactive Li-metal source that mimics Li-powders but has the advantage of being freshly prepared from inexpensive and readily available Li-sources. Here, we report a simple and convenient activation method using liquid ammonia that furnishes a new Li-metal source in the form of crystalline Li-dendrites. The Li-dendrites were shown to have ca. 100 times greater surface area than conventional Li-sources created by prototypical mechanical activation methods. Concomitant with the surface area increase, the Li-dendrites were shown to exhibit significant rate enhancements over Li-powders, which are currently the industry standard for the preparation of organolithium compounds. These features were leveraged for the reproducible synthesis of organolithium reagents over a range of common laboratory scales.
有机锂化学领域长期存在的一个问题是需要一种高反应性的金属锂源，该锂源模拟金属锂粉末，但具有从廉价且易得的锂源新鲜制备的优点。在这里，我们报告了一种使用液氨的简单方便的激活方法，该方法提供了一种新的以结晶锂枝晶形式存在的金属锂源。与传统的由典型机械活化方法制备的锂源相比，锂枝晶的表面积大约大 100 倍。伴随着表面积的增加，锂枝晶表现出比目前用于制备有机锂化合物的工业标准金属锂粉末更高的反应速率。这些特性在一系列常见的实验室规模下，实现了有机锂试剂的可重现合成。
