Gonell Sergio, Caumes Xavier, Orth Nicole, Ivanović-Burmazović Ivana, Reek Joost N H
Homogeneous, Supramolecular and Bio-Inspired Catalysis , Van 't Hoff Institute for Molecular Sciences , University of Amsterdam , Science Park 904 , Amsterdam 1098XH , The Netherlands . Email:
Lehrstuhl für Bioanorganische Chemie , Department Chemie und Pharmazie Friedrich-Alexander-Universität Erlangen , Egerlandstrasse 3 , Erlangen 91058 , Germany.
Chem Sci. 2018 Nov 13;10(5):1316-1321. doi: 10.1039/c8sc03767a. eCollection 2019 Feb 7.
The application of large ML nanospheres allows the pre-concentration of catalysts to reach high local concentrations, facilitating reactions that proceed through dinuclear mechanisms. The mechanism of the copper(i)-catalyzed cyclization of 4-pentynoic acid has been elucidated by means of a detailed mechanistic study. The kinetics of the reaction show a higher order in copper, indicating the formation of a bis-Cu intermediate as the key rate determining step of the reaction. This intermediate was further identified during catalysis by CIS-HRMS analysis of the reaction mixture. Based on the mechanistic findings, an ML nanosphere was applied that can bind up to 12 copper catalysts by hydrogen bonding. This pre-organization of copper catalysts in the nanosphere results in a high local concentration of copper leading to higher reaction rates and turnover numbers as the dinuclear pathway is favored.
大尺寸的金属-有机（ML）纳米球的应用能够使催化剂预富集以达到高局部浓度，从而促进通过双核机制进行的反应。通过详细的机理研究阐明了铜（I）催化4-戊炔酸环化反应的机理。该反应的动力学表明对铜有更高的级数，这表明形成双铜中间体是该反应的关键速率决定步骤。在催化过程中，通过对反应混合物进行化学电离-高分辨质谱（CIS-HRMS）分析进一步鉴定了该中间体。基于机理研究结果，应用了一种ML纳米球，它可以通过氢键结合多达12个铜催化剂。纳米球中铜催化剂的这种预组织导致铜的局部高浓度，由于双核途径更有利，从而导致更高的反应速率和周转数。
