PEG‐DIL‐based MnCl₄²⁻: A novel phase transfer catalyst for nucleophilic substitution reactions of benzyl halides

Abstract

Poly(ethylene glycol) dicationic ionic liquid‐based MnCl42− was prepared by nucleophilic substitution of poly(ethylene glycol) dichloride with methylimidazole followed by reaction with MnCl2. The structural properties of the catalyst were systematically investigated using Fourier transform infrared, UV–visible and Raman spectra and thermogravimetric analysis. The application of this catalyst allows the synthesis of a variety of benzyl thiocyanates and azides in high yield under reflux conditions in water. The main advantages of this method are its easy nature, rapidity, environmental benignity and high yields.

Recent Advances in Imidazolium-Based Dicationic Ionic Liquids as Organocatalysts: A Mini-Review

“…Generally, these molecules are synthesized by nucleophilic substitution of aryl halides in a multiphase environment. With the aim to perform this reaction in water from the perspective of green chemistry, Goodajdar et al developed a PEG-DIL-based MnCl 4 2− ( Figure 8 ) as a phase transfer catalyst [ 54 ].…”

“… Structure of PEG-DIL-based MnCl 4 2− used as phase transfer catalyst, reproduced with permission from [ 54 ]. …”

“… PEG-DIL-MnCl 4 as phase transfer catalyst for the synthesis of benzyl azides ( A ) and thiocyanates ( B ), reproduced with permission from [ 54 ]. …”

One-Step Green Synthesis of Isoeugenol Methyl Ether from Eugenol by Dimethyl Carbonate and Phase-Transfer Catalysts

“…Multiphase reactions are always difficult to conduct, owing to the immiscibility of the phases. However, with the help of an amphiphilic agent, which is soluble in both aqueous and organic phases, such reactions are now possible [ 23 ]. The phase transfer catalyst (PTC) allows transferring substances from one system to another in a chemical reaction between the two non-miscible, heterogeneous systems, which itself has both functional sites to get solubilized in both systems [ 24 ].…”

Selenonium Salt as a Catalyst for Nucleophilic Substitution Reactions in Water: Synthesis of Thiocyanites and Selenocyanates

“…Not surprisingly, the search for methods to prepare these valuable compounds has attracted much attention. They can be prepared, for instance, with the aid of phase transfer catalysts [ 27 , 28 , 29 , 30 , 31 ], in free radical reactions [ 32 , 33 , 34 , 35 ], by electrophilic addition to suitable organic substrates [ 36 , 37 ], or in reactions employing ionic liquids as a solvent and the nucleophilic source of chalcogen cyanide [ 38 ]. In this contribution, we share our findings on the use of selenonium salts to activate substrates such as benzyl bromides through chalcogen bond interactions, facilitating the displacement reaction with KChCN (Ch = S or Se) using a 20:1 mixture of water and dimethyl carbonate as a solvent.…”