Substrate‐Induced Dimerization Assembly of Chiral Macrocycle Catalysts toward Cooperative Asymmetric Catalysis

Abstract

An artificial system of substrate‐induced dimerization assembly of chiral macrocycle catalysts enables a highly cooperative hydrogen‐bonding activation network for efficient enantioselective transformation. These macrocycles contain two thiourea and two chiral diamine moieties and dimerize with sulfate to form a sandwich‐like assembly. The macrocycles then adopt an extended conformation and reciprocally complement the hydrogen‐bonding interaction sites. Inspired by the guest‐induced dynamic assembly, these macrocycles catalyze the decarboxylative Mannich reaction of cyclic aldimines containing a sulfamate heading group. The imine substrate can be activated toward nucleophilic attack of β‐ketoacid by a cooperative hydrogen‐bonding network enabled by sulfamate‐induced dimerization assembly of the macrocycle catalysts. Highly efficient (>95 % yield in most cases) and enantioselective (up to 97.5:2.5 er) transformation of a variety of substrates using only 5 mol % macrocycle was achieved.

Xenon binding by a tight yet adaptive chiral soft capsule

“…Design and synthesis. Recently we have developed a set of chiral tetraamino-bisthiourea macrocycles for substrate-induced assembly asymmetric catalysis 50 . We envisioned that introducing additional carbonyl groups to the diamine moieties on both sides will lead to a type of bisurea-bisthiourea chiral macrocycle M which incorporates multiple hydrogen bond donors (NH) and acceptors (C=S, C=O) simultaneously, and would favor intra-or intermolecular assembly (Fig.…”

Macrocycles in Bioinspired Catalysis: From Molecules to Materials

“…Therefore the unique CO 2 -hosting ability of CB (6) played the critical role in the catalysis. Also, an efficient enantioselective reaction was reported by Wang’s group, showing that chiral macrocyclic compounds with delicate hydrogen-bonding network could conduct an artificial dimerization ( Guo et al, 2020 ). The catalytic cavity based on the macrocyclic compounds was achieved by dimerization for the catalytic reaction ( Figure 2 ).…”

A Photosensitive Cationic Macrocycle Based on Triphenylamine as Photocatalysts for Selective Photooxidation of Phosphines, Styrenes, and Hydroazobenzenes

“…Since the first macrocycle crown ether was synthesized by Pederson in 1967, there has been significant progress in the production of fully synthesized macrocycles that offer structural specificity, great selectivity, and host–guest complexation. Up to now, a wide range of macrocycles including cyclodextrins, calixarenes, cucurbiturils, pillararenes, and cyclotriveratrylenes, are documented and have garnered growing interest due to their intriguing structures and versatile functionalities. − These macrocycles have a variety of features and uses, including as molecular recognition, gas storage, mass transportation, and electronics. − Among the many applications of macrocyclic molecules, macrocyclic supramolecular catalysis has gradually attracted extensive attention in recent years, in which several macrocycle and cage compounds with cavities have been utilized as supramolecular catalysts to enable otherwise unfavorable transformations. − However, in these macrocyclic supramolecular catalytic systems, the catalytic process generally happens through the interaction between the substrate and the macrocyclic molecule rather than directly using the macrocyclic molecule as the catalyst. In addition, the commonly employed macrocycles such as crown ethers, cucurbiturils, and cyclodextrins are either transparent to spectroscopy or exhibit low absorption in the UV–vis range.…”