作者:Michael P. Jensen、Emily L. Que、Xiaopeng Shan、Elena Rybak-Akimova、Lawrence Que, Jr.
DOI:10.1039/b603285k
日期:——
Oxygenation of [CuI(6-PhTPA)](SbF6) in acetone at −90 °C produces a short-lived CuIII2(µ-O)2 intermediate that exhibits an oxygen-isotope-sensitive νCu–O mode at 599 cm−1 and an overtone at 1192 cm−1. The formation of this intermediate is very fast and is second-order in copper(I) complex, implying that two copper-containing species interact in the rate-limiting step or in pre-equilibrium steps prior to the rate determining step. The decay of this intermediate was facile even at −90 °C but did not afford any arene hydroxylation product. Interestingly, the effect of introducing a 6-phenyl substituent on the TPA ligand framework differs from that of a 6-methyl substituent, providing access to a bis(µ-oxo)dicopper(III) intermediate in the former and a (µ-1,2-peroxo)dicopper(II) species in the latter.
CuI(6-PhTPA)](SbF6) 在-90 °C的丙酮中发生氧合反应,产生了一种短寿命的 CuIII2(µ-O)2 中间体,它在 599 cm-1 处显示了氧同位素敏感的 νCu-O 模式,在 1192 cm-1 处显示了泛音。这种中间体的形成速度非常快,而且是铜(I)络合物的二阶形成,这意味着两种含铜物质在限速步骤中或在决定速率步骤之前的预平衡步骤中发生了相互作用。即使在 -90 °C 温度下,这种中间产物也很容易衰减,但不会产生任何炔羟化产物。有趣的是,在 TPA 配体框架上引入 6-苯基取代基的效果与引入 6-甲基取代基的效果不同,前者提供了双(µ-氧代)二铜(III)中间体,后者提供了(µ-1,2-过氧代)二铜(II)物种。