Sterically Stabilized End-On Superoxocopper(II) Complexes and Mechanistic Insights into Their Reactivity with O–H, N–H, and C–H Substrates
作者:Sebastian Y. Quek、Suman Debnath、Shoba Laxmi、Maurice van Gastel、Tobias Krämer、Jason England
DOI:10.1021/jacs.1c07837
日期:2021.12.1
Instability of end-on superoxocopper(II) complexes, with respect to conversion to peroxo-bridged dicopper(II) complexes, has largely constrained their study to very low temperatures. This limits their kinetic capacity to oxidize substrates. In response, we have developed a series of bulky ligands, Ar3-TMPA (Ar = tpb, dpb, dtbpb), and used them to support copper(I) complexes that react with O2 to yield [CuI
末端超氧铜 (II) 配合物在转化为过氧桥联二铜 (II) 配合物方面的不稳定性在很大程度上限制了他们在极低温度下的研究。这限制了它们氧化底物的动力学能力。作为回应,我们开发了一系列庞大的配体 Ar 3 -TMPA (Ar = tpb, dpb, dtbpb),并使用它们来支持与 O 2反应生成[Cu II (η 1 - O 2 •– )(Ar 3 -TMPA)] +物质,在所有温度下对二聚化都是稳定的。O 2的结合在低于环境温度时饱和,并且可以通过变暖来逆转。Ar = tpb 和 dpb 系统在 25 °C 时开始氧化,所有三种 [Cu II (η 1 -O 2 •– )(Ar 3 -TMPA)] +配合物在温度≤−20 °C。这为研究这些配合物提供了一个较宽的温度窗口,通过使用广泛的 O-H对 [Cu II (η 1 -O 2 •– )(tpb 3 -TMPA)] +进行广泛的反应动力学测量来利用这一点、N-H