Roth Daniel, Radosevich Alexander T, Greb Lutz
Anorganisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany.
Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States.
J Am Chem Soc. 2023 Nov 8;145(44):24184-24190. doi: 10.1021/jacs.3c08456. Epub 2023 Oct 25.
A series of structurally constrained phosphenium ions based on pyridinylmethylamidophenolate scaffolds are shown to undergo P(III)/P(V) oxidative addition with C-H bonds of alkynes, alkenes, and arenes. Nonactivated substrates such as benzene, toluene, and deactivated chlorobenzene are phosphorylated in quantitative yields. Computational and spectroscopic studies suggest a low-barrier isomerization from a bent to a T-shaped isomer that initiates a phosphorus-ligand-cooperative pathway and subsequent ring-chain tautomerism. Remarkably, C-H bond activations occur reversibly, allowing for reductive elimination back to P(III) at elevated temperatures or the exchange with other substrates.
一系列基于吡啶基甲基酰胺基酚盐支架的结构受限的磷鎓离子被证明能与炔烃、烯烃和芳烃的C-H键发生P(III)/P(V)氧化加成反应。苯、甲苯和钝化的氯苯等未活化底物能以定量产率进行磷酸化反应。计算和光谱研究表明，从弯曲异构体到T形异构体的低势垒异构化引发了磷-配体协同途径以及随后的环链互变异构。值得注意的是，C-H键活化是可逆的，在高温下可还原消除回到P(III)，或与其他底物进行交换。
