Oxocarboxylic Acids

Abstract

The article contains sections titled: 1. Introduction 2. Pyruvic Acid 3. Acetoacetic Acid and Derivatives 3.1. Properties 3.2. Production 3.3. Uses and Economic Aspects 3.4. Toxicology and Environmental Protection 4. Levulinic Acid 5. Acetonedicarboxylic Acid 6. Other Oxocarboxylic Acids

Dual Catalytic Switchable Divergent Synthesis: An Asymmetric Visible-Light Photocatalytic Approach to Fluorine-Containing γ-Keto Acid Frameworks

“…On the basis of our continuous interest in visible-light photoredox catalysis, we successfully developed a visible-light photoredox catalytic enantioselective difluoroalkylation of ketones with commercially available bromodifluoroacetamides to construct a series of γ-keto amides bearing a gem -difluoromethylene group via coupling with chiral Lewis acid catalysis (Scheme a). This mild dual catalytic strategy provides a novel and straightforward method for the synthesis of fluorine-containing gamma -keto acid derivatives that are widely used as precursors for pharmaceuticals and plasticizers and building blocks or starting materials for a wide number of compounds. Furthermore, another kind of valuable fluorine-containing α,β-unsaturated-γ-keto ester was obtained under the similar dual catalytic conditions by only replacing bromodifluoroacetamide with ethyl bromodifluoroacetate as the fluorine resource (Scheme b).…”

Continuous Flow Upgrading of Selected C2–C6Platform Chemicals Derived from Biomass

“…4-Oxopentanoic acid (levulinic acid, LeA, CAS 123-76-2) is one of the simplest and most important oxocarboxylic acids. It was synthesized for the first time in 1840 by Mulder by heating fructose in the presence of hydrochloric acid. ,, LeA was featured as a promising chemical from biomass on the original 2004 publication from the US Department of Energy . It has gained modest commercial importance since the 60s.…”

“…Though LeA can also be produced from petro-based chemicals such as maleic acid, it is mainly produced through the acid-catalyzed dehydration of either 5- ( e.g. , xylose, arabinose) or 6-carbon lignocellulosic carbohydrates according to multistep processes. ,,,, When starting from 5-carbon carbohydrates, the reaction proceeds through the formation of furfural that requires subsequent reductions toward furfuryl alcohol ( 99 ) and eventually LeA, while when starting from 6-carbon carbohydrates, the reaction proceeds most likely through the intermediate formation of HMF (see Scheme ). Isolation of high purity LeA is cumbersome and typically proceeds through distillation .…”

Nature of a Tetrabutylammonium Chloride–Levulinic Acid Deep Eutectic Solvent

“…Levulinic acid (4-oxopentanoic acid, LEV; Figure ) is a natural compound that can be cost-effectively produced from biomass using different approaches. , LEV has been considered to develop platforms in applications such as polymers, pharmaceutical, food industry, synthesis, and catalysis, as well as a precursor for the preparation of high-value compounds into a biorefinery approach . LEV is nontoxic (acute oral toxicity LD 50 = 1850 mg kg –1 ) and moderately eco-toxic and presents suitable environmental properties . The safety assessment of this molecule led to consider it safe, both for human and environmental exposures, and thus it may be considered a sustainable chemistry approach to several technologies. , Therefore, the interest in LEV-based materials and technologies has increased in these last years both in industry and academia with an expected large increase in world market demand in this decade …”