Metalloenzymartige Zeolithe als Lewis‐Säure‐Katalysatoren für die C‐C‐Bindungsbildung

We report the cascade synthesis of five-membered lactones from a biomass-derived triose sugar, 1,3-dihydroxyacetone, and various aldehydes. This achievement provides a new synthetic strategy to generate a wide range of valuable compounds from a single biomass-derived sugar. Among several examined Lewis acid catalysts, homogeneous tin chloride catalysts exhibited the best performance to form carbon-carbon bonds. The scope and limitations of the synthesis of five-membered lactones using aldehyde compounds are investigated. The cascade reaction led to high product selectivity as well as diastereoselectivity, and the mechanism leading to the diastereoselectivity was discussed based on isomerization experiments and density functional theory (DFT) calculations. The present results are expected to support new approaches for the efficient utilization of biomass-derived sugars.

show abstract

Cascade Synthesis of Five‐Membered Lactones using Biomass‐Derived Sugars as Carbon Nucleophiles

Yamaguchi

Matsuo

Motokura

et al. 2016

Chemistry An Asian Journal

View full text Add to dashboard Cite

show abstract

Biocatalyzed C−C Bond Formation for the Production of Alkaloids

2018

View full text Add to dashboard Cite

Traditional methods of chemical synthesis of alkaloids exhibit various problems such as lack of enantioselectivity, the use of toxic chemical and intermediates, and multiple numbers of synthetic steps. Consequently, various enzymatic methods for the formation of CÀC bonds in the alkaloid skeleton have been developed. Herein, we report advances achieved in the enzymatic or chemo-enzymatic synthesis of pharmaceutically important alkaloids that employ three CÀC bond forming enzymes: two Pictet-Spenglerases and the oxidative CÀC bond forming flavoenzyme Berberine Bridge Enzyme. Protein engi-neering studies, improving the substrate scope of these enzymes, and thereby leading to the synthesis of non-natural alkaloids possessing higher or newer pharmacological activities, are also discussed. Furthermore, the integration of these biocatalysts with other enzymes, in multi-enzymatic cascades for the enantioselective synthesis of alkaloids, is also reviewed. Current results suggest that these enzymes hold great promise for the generation of CÀC bonds in the selective synthesis of alkaloid compounds possessing diverse pharmacological properties.

show abstract

Catalysis and Stability Effect of Solvent Alcohol on the C6 Aldose Conversion toward Tetrose

Hou

Yan

et al. 2019

ChemCatChem

View full text Add to dashboard Cite

Conversions of biomass feedstock into various valuable chemicals are of great significance. As a typical route, retro‐aldol condensation of monosaccharide greatly expands the variety of biomass‐derived platform chemicals via a selective C−C splitting. Herein, we describe a solvent‐catalysed strategy to high‐selectively accumulate tetrose (four‐carbon platform chemical) from C6 aldoses via the retro‐aldol/aldol process. We find that alcohol solvents with Lewis acidity facilitate the C−C splitting process of hexose under the catalyst‐free condition. The conversion is the fastest in methanol while it is the slowest in isopropanol. The product distribution is greatly influenced by the alcohols through shifting the equilibrium between tetrose and glycolaldehyde (GA). The addition of catalyst only accelerates the reaction rate, and does not change the product distribution. On the one hand, the acetalization of GA with methanol or ethanol shifts the equilibrium from tetrose toward GA, which results in a low yield of tetrose in methanol or ethanol solvent. On the other hand, tetrose can be well accumulated in isopropanol or n‐butanol, and the yield of tetrose in isopropanol is higher than in n‐butanol because tetrose can be well solvated and stabilized in it. This solvent‐dependent reaction strategy provides a new possibility which contributes to the conversion of biomass feedback into valuable platform chemicals and accumulation of target products by utilizing the solvation effect.

show abstract

scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.

Contact Info

customersupport@researchsolutions.com

10624 S. Eastern Ave., Ste. A-614

Henderson, NV 89052, USA

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.

Blog Terms and Conditions API Terms Privacy Policy Contact Cookie Preferences Do Not Sell or Share My Personal Information

Made with 💙 for researchers

Part of the Research Solutions Family.

Metalloenzymartige Zeolithe als Lewis‐Säure‐Katalysatoren für die C‐C‐Bindungsbildung

Cited by 8 publications

References 84 publications

Cascade Synthesis of Five‐Membered Lactones using Biomass‐Derived Sugars as Carbon Nucleophiles

Cascade Synthesis of Five‐Membered Lactones using Biomass‐Derived Sugars as Carbon Nucleophiles

Biocatalyzed C−C Bond Formation for the Production of Alkaloids

Catalysis and Stability Effect of Solvent Alcohol on the C6 Aldose Conversion toward Tetrose

Contact Info

Product

Resources

About