Polyamide monomers via carbonate-promoted C–H carboxylation of furfurylamine

Abstract

Carbonate-promoted C–H carboxylation provides a streamlined synthesis of polyamide monomers from a lignocellulosic feedstock without using organic reagents.

Novel Routes in Transformation of Lignocellulosic Biomass to Furan Platform Chemicals: From Pretreatment to Enzyme Catalysis

“…Furfulylamines represent an interesting group of compounds that can be produced from the reductive amination of furans. They have numerous applications as starting materials in the synthesis of polyamine biopolymers and pharmaceuticals [105]. 2-Furfurylamine (FFA), a primary amine that can be produced from FA, is often used as a modifier in high performance thermosets due to its crosslinkable furan ring, where the introduction of furan groups can increase the crosslinking densities of the resulting polymer, and further enhance its thermal stability due to the formation of furfurylamine bridges during polymerization [106].…”

A High-Tg Polyamide Derived from Lignocellulose and CO2

“…We recently reported the synthesis of the bicyclic lactam 8oxa-3-azabicyclo[3.2.1]octan-2-one ((±)-1) from furfurylamine using a streamlined route consisting of CO 3 2− -promoted C−H carboxylation, 22−24 hydrogenation, and cyclization (Figure 1). 25 Furfurylamine is synthesized from furfural in a single-step reductive amination with NH 3 and H 2 , and furfural is produced directly from raw lignocellulosic biomass in a process that has been utilized industrially for nearly a century. 26−30 Thus, with our synthesis of (±)-1, all of the carbons are derived from a lignocellulosic feedstock and CO 2 and no organic reagents are used.…”

“…We recently reported the synthesis of the bicyclic lactam 8-oxa-3-azabicyclo[3.2.1]­octan-2-one ((±)- 1 ) from furfurylamine using a streamlined route consisting of CO 3 2– -promoted C–H carboxylation, − hydrogenation, and cyclization (Figure ). Furfurylamine is synthesized from furfural in a single-step reductive amination with NH 3 and H 2 , and furfural is produced directly from raw lignocellulosic biomass in a process that has been utilized industrially for nearly a century. − Thus, with our synthesis of (±)- 1 , all of the carbons are derived from a lignocellulosic feedstock and CO 2 and no organic reagents are used. One previous work has reported polymerizations of (±)- 1 via melt-phase and hydrolytic anionic ring-opening polymerization (AROP) with limited characterization of the polymer structure and properties. − Optimal reported conditions produced a polymer with a M n of 4000 and a T g of 118 °C after a 10 h reaction time.…”

Carbonate-promoted C–H carboxylation of electron-rich heteroarenes

“…We previously showed that simple alkali carbonates (M 2 CO 3 ) can promote C-H carboxylation of very weakly acidic substrates in solvent-free, alkali salt media at elevated temperature. [29][30][31][32] This transformation is particularly useful for converting a monocarboxylate substrate into a dicarboxylate product, where the substrate enables the formation of a molten reaction medium. 33 More recently, we demonstrated that M 2 CO 3 dispersed into mesoporous TiO 2 (M 2 CO 3 /TiO 2 , Fig.…”