Department of Chemistry and Biochemistry, University of Oklahoma, Norman, Oklahoma 73019, USA.
Org Lett. 2012 Jul 6;14(13):3248-51. doi: 10.1021/ol300911a. Epub 2012 Jun 12.
Host-guest complexation between the dicationic viologen 1-tri(ethylene glycol)-1'-methyl-m-xylyl-4,4'-bipyridinium and cucurbit[7]uril (CB7) was studied at pH = 4.5 in water. The stability constants of the mono- and bis-CB7 adducts were determined at 25 °C by UV-vis spectroscopy. Stopped-flow kinetic experiments were performed to measure the formation and dissociation rate constants of the monoadduct: k(1) = (6.01 ± 0.03) × 10(6) M(-1)s(-1) and k(-1) = 52.7 ± 0.4 s(-1), respectively. Possible mechanisms of complexation are discussed in view of the kinetic results.
在 pH = 4.5 的水中研究了二价紫罗精 1-三（乙二醇）-1'-甲基-m-二甲苯-4,4'-联吡啶阳离子与瓜环[7]（CB7）之间的主客体络合作用。通过紫外-可见光谱法在 25°C 下测定了单和双 CB7 加合物的稳定常数。进行了停流动力学实验以测量单加合物的形成和离解速率常数：k(1) = (6.01 ± 0.03) × 10(6) M(-1)s(-1)和 k(-1) = 52.7 ± 0.4 s(-1)。根据动力学结果讨论了络合的可能机制。
