C(sp²)−C(sp²) Coupling in Water: Palladium(II) Complexes of N‐Pincer Tetradentate Porphyrins as Effective Catalysts

Abstract

Ac onvenient and efficient palladium(II)-porphyrin catalytic system has been developed for the Suzuki-Miyaura cross-coupling (SMC) of aryl bromides with potassium aryltrifluoroborate in water.Aseries of seven different porphyrins and their complexes with palladium (Pd II (por)-1-Pd II (por)-7) were prepared, and screenedt heir catalytic activity in making biaryls through C(sp 2 )ÀC(sp 2 )c oupling.S ignificantly, the present protocol utilizes safe, water-soluble, and highly stable porphyrins as an alternative to toxic and unstable phosphine ligands. Thes imple preparation of porphyrins and their complexes, use of moisture-resistantc atalyst, excellent yields of the isolated products,u se of eco-friendly solvent( such as water), and reusability of the catalysta re the notable advantages of this method. This finding uses marginally explored, moisture-insensitive potassium phenyltrifluoroborates as nucleophilesf or SMC. Furthermore, the scope of the methodh as been demonstrated for the multigram scale preparation of biaryls without any side products.Supporting information and the ORCID identification number(s) for the author(s) of this article can be found under http://dx.

Rapid Suzuki-Miyaura Couplings with ppm Level of Palladium Catalyst in a High-Pressure and High-Temperature Water System

“…Increasing concerns about the development of sustainable chemical technologies, mean there have been huge demands for processes which combine high production efficiency with low environmental burden, process safety, and economic viability. From this perspective, utilization of water as a reaction medium would be one of the most attractive solutions for a chemical process [1][2][3][4][5][6][7]. Water is highly abundant, chemically stable, non-toxic, cost-effective and safe compared with most volatile organic solvents used in traditional chemical synthesis.…”

Palladium‐catalysed room‐temperature Suzuki–Miyaura coupling in water extract of pomegranate ash, a bio‐derived sustainable and renewable medium

“…Even though several hundreds of studies have appeared in the literature, it remains unanswered, even for a simple case, which procedure or catalyst is the best one . On the other hand, several new methodologies have still appeared using several modified conditions including ligands, catalysts, solvent, additives, etc . In this connection and in continuation of our recent research on the development of benign methodologies for C–C coupling, we report here an effective method for SMC using a natural feedstock, water extract of pomegranate ash (WEPA), as a green and sustainable (basic) medium.…”

“…On the other hand, several new methodologies have still appeared using several modified conditions including ligands, catalysts, solvent, additives, etc . In this connection and in continuation of our recent research on the development of benign methodologies for C–C coupling, we report here an effective method for SMC using a natural feedstock, water extract of pomegranate ash (WEPA), as a green and sustainable (basic) medium. Indeed, this method with inherent safeness and renewability can further strengthen the scope of the use of naturally derived (basic) media for C–C cross‐couplings, especially in SMC.…”

Added catalyst-free, versatile and environment beneficial bromination of (hetero)aromatics using NBS in WEPA

“…The nuclear bromination of aromatic or heteroaromatic compounds is the frequently used transformation in making highly reactive aryl/heteroaryl bromides. These bromides are the principal substrates in the synthesis of biaryls, aryl amines, organometallics, cinnamate esters, functional materials and diverse biologically effective organics [1][2][3][4][5][6][7]. By virtue of this essentiality a sizeable efforts have been appeared in the literature for the preparation of aryl bromides and heteroaryl bromides.…”