We have previously postulated a serine gated electron transfer hypothesis (Inorg. Chem, 2002, 41, 1281–1291) to possibly be involved in gating electron transfer between the Mo(V) and Mo(IV) states. In this study we explored the effect of solvent dielectric upon the rate and mechanism of isomerization of an oxo-Mo(V) core in attempt to understand the effect of solvent polarity to the isomerization reaction. To this end, the data suggests that there may be significant entropic contributions to the reorganization of metal center as a function of the local dielectric constant. Furthermore, we note that there is a change in the observed rate as well as the mechanism of the geometric rearrangement when it is examined in polar and non-polar environments. More specifically, in low dielectric media, the reaction proceeds either via a fast dissociation which is then followed by a twist mechanism or by a dissociation that is synchronized with the twist mechanism.
我们之前假设
丝氨酸门控电子转移假说 (Inorg. Chem, 2002, 41, 1281–1291) 可能参与 Mo(V) 和 Mo(IV) 态之间的门控电子转移。在本研究中,我们探讨了溶剂电介质对氧代-Mo(V)核异构化速率和机制的影响,试图了解溶剂极性对异构化反应的影响。为此,数据表明,作为局部介电常数的函数,可能对
金属中心的
重组有显着的熵贡献。此外,我们注意到,当在极地和非极地环境中进行检查时,观察到的速率以及几何重排的机制发生了变化。更具体地,在低介电介质中,反应要么通过快速解离,然后进行扭曲机制,要么通过与扭曲机制同步的解离进行。