Bio-based amines through sustainable heterogeneous catalysis

Abstract

Heterogeneous catalysis offers a sustainable toolbox for the synthesis of a wide variety of biomass-derived amines.

Selectivity Control in Catalytic Reductive Amination of Furfural to Furfurylamine on Supported Catalysts

“…At the lowest ammonia concentration in Figure (1 : 1 ammonia to furfural ratio), a loss of selectivity to the secondary amine is observed over Pd/SiO 2 , alongside a sudden increase in the formation of alcohols (FOL and THFA). At these reaction conditions, the alcohol pathway is in parallel to the rest of the reaction network (step A in Figure ), as alcohol amination is known to be significantly more challenging than aldehyde reductive amination . Further, reactions run under identical conditions to those in Table using FOL as the starting substrate yield no detectable amine products.…”

“…Ru/ZrO 2 was used in amination of a variety of aldehydes and ketones derived from biomass by Liang et al., who achieved >90 % yields of several different primary amines with this ruthenium catalyst (though FAM was not the target molecule) . The group also achieved a 6–7 % yield of ethylenediamine from glycolaldehyde using the same Ru/ZrO 2 catalyst, which is an achievement because primary amine production (and especially primary diamines) is significantly more challenging from alcohols than from aldehydes or ketones, as most often the mechanism requires an initial dehydrogenation of the alcohol to the aldehyde/ketone before aldehyde/ketone reductive amination takes place . In alcohol amination, typically the same hydrogen atoms removed from the alcohol molecule are used to hydrogenate the imine .…”

Selective Transformations of Triglycerides into Fatty Amines, Amides, and Nitriles by using Heterogeneous Catalysis

“…The alarming predictions of the rapid depletion of fossil‐fuel resources have inspired researchers to develop alternative technologies that exploit renewable energy sources . Many studies have focused on the conversion of lignocellulosic biomass and triglycerides into various platforms of value‐added chemicals . Industrially, triglycerides in oils and fats have been used as feedstocks for the synthesis of fatty amines, amides, nitriles, and alcohols, which in turn are used for the production of surfactants, polymers, and other useful commodity chemicals …”

Morphology‐Tuned Activity of Ru/Nb2O5 Catalysts for Ketone Reductive Amination

“…Generally, there are three typical amination approaches: amination of halides,hydrogen‐borrowing amination of alcohol or phenol,and the reductive amination of ketone or aldehyde . The reaction from halides to amines has been well established . However, in this strategy some strict conditions are often required and the formation of the toxic and environmentally unfriendly by‐products is also inevitable .…”