Synthesis of polyamides using palladium-on-carbon (Pd/C) as a heterogeneous, reusable and ligand-free catalytic system

Abstract

Polyamide has been synthesized by using Pd/C as a heterogeneous, phosphine-free and reusable catalytic system. The catalyst solves the basic problem of catalyst recovery and furnishes good to excellent yield of polyamides.

Development of the Applications of Palladium on Charcoal in Organic Synthesis

“…For example Bhanage's group used Pd/C as a heterogeneous, efficient and recyclable catalyst for the synthesis of various polyamides via the carbonylation–polycondensation reaction of diamines with aromatic diiodides under CO [Eq. (46)] . The Pd/C catalyst was recycled at least five times without any loss of activation by a simple filtration process.…”

Ligand-free Pd(0)/SiO2-catalyzed aminocarbonylation of aryl iodides to amides under atmospheric CO pressure

“…Different substituted amines were also tested. Good yields of 84% to 99% were obtained for the amines with electron-donating groups (entries [12][13][14][15][16]. It is noteworthy that p-substituted amines gave a slightly decreased yield compared with that of o-and m-substituted amines.…”

“…In the absence of catalyst, no product was obtained. In the case of only using Pd/ SiO 2 without K 2 CO 3 , a small amount of the desired product (10%) was obtained ( supports provided the desired product in moderate to good yields (from 42% to 84%) under similar reaction conditions (entries [11][12][13][14][15][16][17][18]. Therefore, Pd/SiO 2 catalyst was found to be the optimum catalyst for the carbonylation of iodobenzene.…”

“…Various heterogeneous palladium catalysts have been reported for the synthesis of amides by aminocarbonylation of aryl halide with CO gas using a support such as silica, carbon, ZIF-8, MCM-41, ionic liquid phases and organic polymers. [12][13][14][15][16][17][18][19] However, these carbonylation reactions over supported palladium catalysts proceeded at high CO pressure and high reaction temperature. Dang group have reported the atmospheric pressure aminocarbonylation of aryl iodides using palladium nanoparticles supported on MOF-5 at 120 C.…”

Supported Palladium Catalyzed Carbonylative Coupling Reactions using Carbon Monoxide as C1 Source

“…Furthermore, the group also synthesized polyamides using Pd/C as heterogeneous catalysts using carbonylative polycondensation of diiodides, diamines and carbon monoxide (Scheme 20). [41] The catalyst can be recycled up to five cycle without substantial fall in catalytic activity. In continuation to this work, they have also published Pd/C catalyzed synthesis of polyester amides in appreciable yields following similar strategy (Scheme 21).…”