Recent Developments of Heterogeneous Catalysts for Hydrogenation of Carboxylic Acids to their Corresponding Alcohols

Abstract

Hydrogenation of carboxylic acids is an important organic reaction for the synthesis of alcohols, aldehydes, alkanes, and so on. Selective hydrogenation of carboxylic acids to alcohols is particularly important because alcohols are useful and valuable chemicals. However, the hydrogenation of carboxylic acids is difficult due to the low reactivity of the carboxy group and the acidic property, which require rational design of catalysts. Up to now, various effective homogeneous and heterogeneous catalysts have been intensively developed, and remarkable advances have been made in heterogeneous catalysts. In this minireview, recent progress (2010 and after) on the development of heterogeneous catalysts for hydrogenation of carboxylic acids to alcohols, particularly for monocarboxylic acids to mono primary alcohols, is reviewed. The reported literatures were categorized in terms of catalyst systems, such as monometallic catalysts and bimetallic catalysts. The characteristics, particularly the structure of active sites, reaction mechanism and stability, were introduced.

Rhenium – A Tuneable Player in Tailored Hydrogenation Catalysis

“…The hydrogenation of carboxylic acids and their corresponding esters is an important class of reaction used to produce relevant chemicals. Rhenium‐based heterogeneous catalysts have been studied as excellent choices for these reactions [79,105] . Regarding monometallic rhenium, Toyao et al.…”

Catalytic Hydrogenation of Thioesters, Thiocarbamates, and Thioamides

“…In the context of producing high-value chemicals from bio-based feedstocks through more sustainable methods, hydrogenation of carboxylic acids and their derivatives is of great importance for generating versatile organic building blocks in a waste-free fashion, as compared to traditional reducing methods using hydride reagents. 5 Recent years have witnessed great progress in this area using H 2 in transforming carboxylic acids, 6 esters, 7 amides, 8 and even carbonates, carbamates, and ureas 9 to a vast number of alcohols and amines. Nonetheless, to the best of our knowledge, the hydrogenation of thioesters is yet to be reported, 10 possibly due to the generation of thiols which might retard typical metal-catalyzed hydrogenation systems.…”

Reductive Conversion of Biomass-Derived Furancarboxylic Acids with Retention of Carboxylic Acid Moiety

“…The combination of Rh and WO x shows the highest ratio of formation amount of C-O hydrogenolysis products (DVL + 5-HVA) to that of carboxylic acid hydrogenation products (tetrahydrofurfuryl alcohol, 1,5-pentanediol and 1-pentanol). MoO x and ReO x species are known to have activity or promotion ability in carboxylic acid hydrogenation, especially when combined with Rh, and these characters lower the formation amount ratio of C-O hydrogenolysis products to carboxylic acid hydrogenation products (8) [ [70][71][72][73][74][75]. However, the ratio is still lower than 1 even at low conversion level over Rh-WO x /SiO 2 catalyst.…”