Current Organic Chemistry - Volume 25, Issue 2, 2021

Formic acid (HCOOH) as an inexpensive and versatile reagent has gained broad attention in the field of green synthesis and chemical industry. Formic acid acts not only as a convenient and less toxic CO surrogate, but also as an excellent formylative reagent, C1 source and hydrogen donor in organic reactions. Over the past decades, many exciting contributions have been made which have helped chemists to understand the mechanisms of these reactions. The review will examine recent advances in the utilization of formic acid as an economical, practical and multipurpose reactant in synthetic transformations.

Perimidines are nitrogen-containing heterocyclic scaffolds with a wide range of biological and material properties. Several synthetic transformations on perimidines afford fused heterocycles. This review focuses on every aspect of perimidines, including different synthetic procedures, reactions and applications, and covers the literature published up to the year 2020, using more than 170 references.

As compared with widely used polyolefin materials, aliphatic polyesters have been primarily used in electronics, packaging, and biomedicine owing to its unique biocompatibility and degradability. At present, ring-opening polymerization (ROP) of lactone is the main method to synthesize polyesters. Two types of catalysts, including metal-based catalysts and organocatalysts, were most researched today. However, metal-based catalysts lead to polymer materials with metal residues, which limits its properties and applications. As a result, organocatalysts have received great attention. In this review, the progress of organocatalytic ring-opening polymerization in the past decades was systematically summarized. The potential challenges and development directions in this field are also discussed.

The copolymers of carbon monoxide (CO) and olefins, namely polyketones, are a family of widely used materials. In the catalytic preparation of these materials, palladium(II) catalysts represent the most successful catalytic systems. The production of both alternating and non-alternating polyketones has been achieved, with a great difference in their physical properties. Herein, a variety of palladium(II) catalysts, employed for the copolymerization of CO with various olefinic monomers, such as ethylene, α -olefins, styrene and polar vinyl monomers, are fully summarized. The influence of important factors, such as solvents and counterions on specific copolymerization, is also discussed. This review aims to enlighten the design of new Pd catalysts with improved properties, as well as the development of new polyketone materials.

As a phosphorus scaffold, hexachlorocyclotriphosphazene (HCCP) is widely used for the synthesis of varieties of derivatives, including metal-binding complexes and several unique organometallic compounds, which exhibit potential catalytic, flame retardant and biological activities. Some metal-binding HCCP derivatives have shown antibacterial activities as free ligands and metal complexes. These derivatives can also serve as building blocks for the formation of antibacterial metal-containing polymers. This mini-review is focused on the design and development of HCCP derivatives as potential antibacterial agents with representative examples as well as antibacterial mechanisms from recent years.

The results of studies over the past ten years in the field of C=C bond hydrogenation in the presence of palladium catalysts deposited on various inorganic and organic carriers such activated carbons, carbon nanotubes, alumina, zeolites, or composite materials based on Al2O3-SiO2, polystyrene, polypropyleneimine, polyamidoamine and hybrid inorganic/ polymer-carriers, are presented. The selectivity and rates of the hydrogenation process are considered and some comparisons are made. Porous supports and containing dendrimers generally retain palladium particles more effectively. Nanosized palladium stabilized by different dendrimers catalyzes the hydrogenation of C=C bonds in polyfunctional compounds chemoselectively without affecting functional groups, such as CHO, C=O, C(O)OR, CN, NO2, and halogens.