Abstract：
Although carbanions, which are usually regarded as reactive species and powerful metalation reagents, can be stabilized through choice of the substitution pattern, they have rarely been considered for the design of weakly coordinating anions (WCA). Here, we report on an evaluation of the potential of a series of differently substituted carbanions to serve as WCA by computational methods. This led us to the synthesize the water- and air-stable allyl anion 1 with triflyl and 3,5-bis(trifluoromethyl)phenyl (ArF) moieties, which can be isolated in high yields even on a gram-scale. Single crystal X-ray crystallography and NMR studies confirmed the weak coordination ability of the anion by showing negligible or only weak interactions with different cations. This property enabled the application of 1 in the stabilization of reactive group 14 and 15 cations. In addition to the crystallization of a phosphenium cation, the first all-carbon salt with a non-aromatic carbanion is reported, which revealed to be a convenient reagent for hydride abstraction such as from silanes. Overall, this work demonstrates the so far untapped potential of carbanions as WCA, that are accessible with a variety of different cations for various applications.
摘要：
虽然碳阴离子，通常被认为是活性物质和强大的金属化试剂，可以通过选择替代模式来稳定，它们很少被考虑用于弱配位阴离子（WCA）的设计。这里,我们报告了通过计算方法评估一系列不同取代的碳阴离子作为WCA的潜力。这导致我们合成了具有三氟甲基和3,5-双（三氟甲基）苯基（ArF）部分的水和空气稳定的烯丙基阴离子1，即使在克尺度上也可以高产率分离。单晶X射线晶体学和NMR研究通过显示与不同阳离子的可忽略或仅弱相互作用来证实阴离子的弱配位能力。该性质使得能够在反应性基团14和15阳离子的稳定中应用1。除了磷阳离子的结晶，据报道，第一种具有非芳香族碳负离子的全碳盐，这表明它是一种方便的氢化物提取试剂，例如从硅烷中提取。总的来说,这项工作证明了碳阴离子作为WCA迄今尚未开发的潜力，可与各种不同的阳离子为各种应用。
