Trifunctional Metal Ion-Catalyzed Solvolysis: Cu(II)-Promoted Methanolysis of <i>N</i>,<i>N</i>-bis(2-picolyl) Benzamides Involves Unusual Lewis Acid Activation of Substrate, Delivery of Coordinated Nucleophile, Powerful Assistance of the Leaving Group Departure
作者:Mark A. R. Raycroft、Christopher I. Maxwell、Robyn A. A. Oldham、Areen Saffouri Andrea、Alexei A. Neverov、R. Stan Brown
DOI:10.1021/ic301454y
日期:2012.10.1
decomposition of the 4-nitro and 4-methoxy derivatives, 4b:Cu(II):(−OCH3)(HOCH3) and 4g:Cu(II):(−OCH3)(HOCH3), in the plateau region of the sspH/log(kx) profiles in both CH3OH and CH3OD. Activation parameters for decomposition of these complexes are ΔH⧧ = 19.1 and 21.3 kcal mol–1 respectively and ΔS⧧ = −5.1 and −2 cal K–1 mol–1. Density functional theory (DFT) calculations for the reactions of the Cu(II):(−OCH3)(HOCH3)
在25℃下,在s s的pH值控制下,研究了在芳环上带有取代基X的一系列N,N-双(2-吡啶甲基)苯甲酰胺(4a – g)的Cu(II)配合物的甲醇酶。该络合物的活性形式在中性s s pH下的化学计量比为4:Cu(II):( - OCH 3)(HOCH 3),并以速率常数k x单分子分解。日志的哈米特图(ķ X)与σ X值具有ρ X为0.80±0.05。对于4-硝基和4-甲氧基衍生物4b:Cu(II):( - OCH 3)(HOCH 3)和4g:Cu(II):( - OCH 3)(HOCH 3),在CH 3 OH和CH 3 OD的s pH / log(k x)曲线的平稳区域。对于这些配合物的分解激活参数Δ ħ ⧧ = 19.1和21.3千卡摩尔-1分别和Δ小号⧧= −5.1和-2 cal K –1 mol –1。进行了密度泛函理论(DFT)计算4a,b和g(4a,X = 3,5-dinitro)的Cu(II):(