Palladium Grafted Functionalized Nanomaterial: An Efficient Catalyst for the CO₂ Fixation of Amines and Production of Organic Carbamates

Abstract

Chemical fixation of carbon dioxide through suitable catalytic pathways is very demanding in the context of sustainable environment. An environmentally benign synthetic studies of N‐formylated amine derivatives by carbon dioxide fixation of amines have been investigated in presence of Merrifield resin supported palladium nanomaterial (Pd‐PS‐amtp catalyst) at ambient temperature. Poly(methylhydrosiloxane) was employed as a susceptible hydride transferring agent in the present CO2 fixation reaction. Further this catalyst exhibited an extended catalytic activity for the production of organic carbamates from dimethyl carbonate and aromatic amines. The Pd‐PS‐amtp nanomaterial has been produced by two step strategies and systematically characterized by FTIR, UV‐Vis, FE‐SEM and TGA‐DTA analysis. The benefits of this system are quite economical, high recycling efficiency and consuming short reaction time to allow significant product yield. The production of organic carbamates in presence of the present catalyst is a phosgene‐free procedure where dimethyl carbonate (DMC) is utilized both as carboxylating agent and solvent. The recovery of Pd‐PS‐amtp nanomaterial could easily be performed after the reactions and recyclable up to six times without considerable reduction in catalytic activity.

Autocatalytic Green Synthesis of Imines in Traceless Medium

“…Reduction of sulfoxides and N-oxides, [34] α-alkylation of amines, [35] asymmetric α-allylation of branched ketones, [36] synthesis of non-symmetric α-diketones, [37] oxidative dehydrogenation of amines [38] and alcohols [39] and selective O-acylation of benzylic alkanolamines [40] proceeded with CO 2 assistance. Direct chemical fixation and catalytic reduction of carbon dioxide lead to the valuable compounds such as carbamates, [41] cyclic carbonates [42,43] and C1-products (methanol, formic acid, etc.). [44] However, previously reported CÀ C bond forming processes like aldol, [45] Knoevenagel, [46] Henry, [47] Michael [48] and Diels-Alder reactions [49][50][51][52] proceed in sc-CO 2 only in the presence of catalysts or under harsh conditions.…”

“…Reduction of sulfoxides and N‐oxides, [34] α‐alkylation of amines, [35] asymmetric α‐allylation of branched ketones, [36] synthesis of non‐symmetric α‐diketones, [37] oxidative dehydrogenation of amines [38] and alcohols [39] and selective O ‐acylation of benzylic alkanolamines [40] proceeded with CO 2 assistance. Direct chemical fixation and catalytic reduction of carbon dioxide lead to the valuable compounds such as carbamates, [41] cyclic carbonates [42,43] and C1‐products (methanol, formic acid, etc .) [44] .…”

A study of contemporary progress relating to COF materials for CO2capture and fixation reactions

“…CO 2 is a non-toxic, renewable, inexpensive, and abundant raw C1 feedstock, and it can act as a C1 building block for the synthesis of various valuable chemicals with added economic value, such as carbonates, carbamates, urea, etc. 4–7 Different types of catalysts can be designed for this purpose, like porous organic polymers (POPs), metal organic frameworks (MOFs), covalent organic frameworks (COFs), oxide-based compounds, ionic liquids, etc. 4–9 The designed catalysts should be selective, stable, easily recoverable from the reaction medium, durable, and highly efficient for industrial applications.…”

“…4–7 Different types of catalysts can be designed for this purpose, like porous organic polymers (POPs), metal organic frameworks (MOFs), covalent organic frameworks (COFs), oxide-based compounds, ionic liquids, etc. 4–9 The designed catalysts should be selective, stable, easily recoverable from the reaction medium, durable, and highly efficient for industrial applications. Lots of catalytic systems have been reported for the conversion of CO 2 to value-added products, but at present they are unsuitable due to the need for harsh reaction conditions, facing issues like high reaction pressures, difficulties in recoverability, high production costs, etc.…”

From ‘Gift’ to gift: producing organic solvents from CO2

“…In the transformation, DMF could be produced in 86% yield by using dimethylamine aqueous solution as the starting reagent. Another heterogeneous Pd-catalyzed CO 2 fixation of amine to prepare DMF was described by Islam and coworkers, which utilized Merrifield resin supported palladium nanomaterial (Pd-PS-amtp catalyst) as a catalyst and poly (methylhydrosiloxane) (PMHS) as a hydride transferring agent 69. Vorholt and co-workers demonstrated a ruthenium-catalyzed synthesis of DMF from CO 2 in a biphasic solvent system (Scheme 12) 70.…”