scholarly journals Recent advances in phosphoranyl radical-mediated deoxygenative functionalisation

2020 ◽  
Vol 7 (16) ◽  
pp. 2319-2324 ◽  
Author(s):  
Xiao-Qiang Hu ◽  
Ye-Xing Hou ◽  
Zi-Kui Liu ◽  
Yang Gao
Keyword(s):  
Carboxylic Acids ◽  
Building Blocks ◽  
Recent Advances ◽  
Phosphoranyl Radical

Alcohols and carboxylic acids have been established as versatile building blocks in the assembly of various carbon frameworks.

α-Aminoboronates: recent advances in their preparation and synthetic applications

2021 ◽  
Author(s):  
Wenbo Ming ◽  
Harjeet S. Soor ◽  
Xiaocui Liu ◽  
Alina Trofimova ◽  
Andrei K. Yudin ◽  
...  
Keyword(s):  
Building Blocks ◽  
Synthetic Methods ◽  
Mechanistic Explanations ◽  
Recent Advances

This review summarizes new methodology for the synthesis of α-aminoboronates, including asymmetric synthetic methods and mechanistic explanations of reactivity. Applications of α-aminoboronates as versatile synthetic building blocks are also discussed.

scholarly journals NaIO4/Br- as a mild system for the oxidation of 1-methyl-anthra-9,10-quinones

2015 ◽  
Author(s):  
Marcin Cybulski ◽  
Adam Formela ◽  
Katarzyna Sidoryk ◽  
Olga Michalak ◽  
Anna Rosa ◽  
...  
Keyword(s):  
High Pressure ◽  
Carboxylic Acids ◽  
Scale Up ◽  
Lithium Bromide ◽  
Cost Effective ◽  
Building Blocks ◽  
Multidrug Resistant ◽  
Resistant Cell ◽  
Direct Oxidation ◽  
Reaction Conditions

One of the anthraquinone classes comprises compounds with a carbonyl group. These natural or synthetic anthraquinones find their application as building blocks in the synthesis of the compounds with a biological activity. Recently, 4-substituted anthra-9,10-quinone-1-carboxylic acids (2) have been used as key intermediates in the synthesis of patented compounds (3) with anticancer activity against multidrug resistant cell lines. Although 2,7-dihydro-3H-dibenz[de,h]cinnolin-3,7-diones (3) were successfully synthetized in a small laboratory scale, several problems were observed during the preparation of their acid intermediates (2) in a multi-gram scale. The known methods for the preparation of 2 are based on the oxidation of the methyl group in anthra-9,10-quinones (1). The most common are: the oxidation with the diluted nitric acid under high pressure in a sealed tube at the temperature of 195-220 oC, the oxidation in nitrobenzene by passing chlorine gas through the reaction mixture at the temperature of 160-170 oC or in a presence of the fuming sulphuric acid. The mentioned methods require aggressive reagents and specific reaction conditions including high pressure and temperature. Thus, there was a need to find a new efficient, cost-effective and reproducible synthetic method of preparation of 2. While searching literature it was found that the direct oxidation of alkylarenes mediated by the sodium periodate/lithium bromide combination produces benzyl acetates throughout benzyl bromides in the acetic acid, or benzylic acids in the diluted inorganic acid. Based on these results we examined a variety of reaction conditions with or without the bromine source and the oxidizing anion. As a result, a novel procedure for the preparation of highly pure 4-substituted anthra-9,10-quinone-1-carboxylic acids (HPLC > 99.5%) using oxidizing anion/ brominating reagent system was developed. It enabled 2 isolation by the simple filtration of the reaction mixture and was applied in the scale-up of 2,7-dihydro-3H-dibenz[de,h]cinnolin-3,7-dione derivatives.

scholarly journals Palladium(II)-Catalyzed C(sp3)–H Activation of N,O-Ketals towards a Method for the β-Functionalization of Ketones

Synlett ◽  
2019 ◽  
Vol 30 (04) ◽  
pp. 454-458 ◽  
Author(s):  
Danny Ho ◽  
Jonas Calleja ◽  
Matthew Gaunt
Keyword(s):  
Carboxylic Acids ◽  
Functional Groups ◽  
Building Blocks ◽  
Activation Pathway ◽  
Bond Forming ◽  
Aliphatic Ketones ◽  
Palladium Catalyzed

A method for the formal β-functionalization of aliphatic ketones via a palladium-catalyzed sp3 C–H activation pathway is reported. An N,O-ketal directs an aliphatic C–H carbonylation to form γ-lactams which upon hydrolysis generate γ-keto carboxylic acids. This C–C bond-forming reaction is tolerant of a range of functional groups, enabling the synthesis of a range of synthetically important building blocks. Furthermore, the concepts underlying this transformation have also enabled the development of a related C–H alkenylation process to highly functionalised heterocycles.

scholarly journals Recent Advances in Glycerol Catalytic Valorization: A Review

Catalysts ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 1279
Author(s):  
Manuel Checa ◽  
Sergio Nogales-Delgado ◽  
Vicente Montes ◽  
José María Encinar
Keyword(s):  
Activated Carbon ◽  
Carboxylic Acids ◽  
Large Scale ◽  
Biodiesel Production ◽  
Added Value ◽  
Scale Production ◽  
Recent Advances ◽  
Large Scale Production ◽  
Wide Range ◽  
Technological Limitations

Once a biorefinery is ready to operate, the main processed materials need to be completely evaluated in terms of many different factors, including disposal regulations, technological limitations of installation, the market, and other societal considerations. In biorefinery, glycerol is the main by-product, representing around 10% of biodiesel production. In the last few decades, the large-scale production of biodiesel and glycerol has promoted research on a wide range of strategies in an attempt to valorize this by-product, with its transformation into added value chemicals being the strategy that exhibits the most promising route. Among them, C3 compounds obtained from routes such as hydrogenation, oxidation, esterification, etc. represent an alternative to petroleum-based routes for chemicals such as acrolein, propanediols, or carboxylic acids of interest for the polymer industry. Another widely studied and developed strategy includes processes such as reforming or pyrolysis for energy, clean fuels, and materials such as activated carbon. This review covers recent advances in catalysts used in the most promising strategies considering both chemicals and energy or fuel obtention. Due to the large variety in biorefinery industries, several potential emergent valorization routes are briefly summarized.

scholarly journals Modular triazine-based carborane-containing carboxylic acids – synthesis and characterisation of potential boron neutron capture therapy agents made of readily accessible building blocks

2019 ◽  
Vol 48 (29) ◽  
pp. 10834-10844 ◽  
Author(s):  
Martin Kellert ◽  
Dennis J. Worm ◽  
Paul Hoppenz ◽  
Menyhárt B. Sárosi ◽  
Peter Lönnecke ◽  
...  
Keyword(s):  
Carboxylic Acid ◽  
Carboxylic Acids ◽  
Boron Neutron Capture Therapy ◽  
Neutron Capture ◽  
Building Blocks ◽  
Neutron Capture Therapy ◽  
Boron Neutron Capture

Boron-rich carboxylic acid derivatives were synthesised as coupling partners for tumour-selective biomolecules with applications as selective BNCT agents.

scholarly journals Recent Advances in Palladium-Catalyzed Isocyanide Insertions

Molecules ◽  
2020 ◽  
Vol 25 (21) ◽  
pp. 4906
Author(s):  
Jurriën W. Collet ◽  
Thomas R. Roose ◽  
Bram Weijers ◽  
Bert U. W. Maes ◽  
Eelco Ruijter ◽  
...  
Keyword(s):  
Organic Synthesis ◽  
Building Blocks ◽  
Insertion Reactions ◽  
Chemical Reagents ◽  
The Past ◽  
Recent Advances ◽  
Recent Developments ◽  
Palladium Catalyzed ◽  
Made In ◽  
Rapid Incorporation

Isocyanides have long been known as versatile chemical reagents in organic synthesis. Their ambivalent nature also allows them to function as a CO-substitute in palladium-catalyzed cross couplings. Over the past decades, isocyanides have emerged as practical and versatile C1 building blocks, whose inherent N-substitution allows for the rapid incorporation of nitrogeneous fragments in a wide variety of products. Recent developments in palladium catalyzed isocyanide insertion reactions have significantly expanded the scope and applicability of these imidoylative cross-couplings. This review highlights the advances made in this field over the past eight years.

Amino acid transportation, sensing and signal transduction in the mammary gland: key molecular signalling pathways in the regulation of milk synthesis

2020 ◽  
Vol 33 (2) ◽  
pp. 287-297
Author(s):  
Zhihui Wu ◽  
Jinghui Heng ◽  
Min Tian ◽  
Hanqing Song ◽  
Fang Chen ◽  
...  
Keyword(s):  
Amino Acids ◽  
Mammary Gland ◽  
Milk Protein ◽  
Building Blocks ◽  
Branched Chain Amino Acids ◽  
Signalling Pathways ◽  
Recent Advances ◽  
Branched Chain ◽  
Molecular Signalling Pathways

AbstractThe mammary gland, a unique exocrine organ, is responsible for milk synthesis in mammals. Neonatal growth and health are predominantly determined by quality and quantity of milk production. Amino acids are crucial maternal nutrients that are the building blocks for milk protein and are potential energy sources for neonates. Recent advances made regarding the mammary gland further demonstrate that some functional amino acids also regulate milk protein and fat synthesis through distinct intracellular and extracellular pathways. In the present study, we discuss recent advances in the role of amino acids (especially branched-chain amino acids, methionine, arginine and lysine) in the regulation of milk synthesis. The present review also addresses the crucial questions of how amino acids are transported, sensed and transduced in the mammary gland.

Recent Progress on Radical Decarboxylative Alkylation for Csp3–C Bond Formation

Synthesis ◽  
2017 ◽  
Vol 49 (24) ◽  
pp. 5263-5284 ◽  
Author(s):  
Hongli Bao ◽  
Yajun Li ◽  
Liang Ge ◽  
Munira Muhammad
Keyword(s):  
Carboxylic Acids ◽  
Recent Progress ◽  
Bond Formation ◽  
Stepping Stone ◽  
Recent Advances ◽  
Aliphatic Carboxylic Acids ◽  
Further Development

Radical decarboxylation has emerged as an attractive method for the formation of C–C bonds starting from easily accessible carboxylic acids. In this review, we attempt to bring the readers up to date in this rapidly expanding field. Specifically, we will cover recent advances in Csp3–C bond formation via the radical decarboxylation of aliphatic carboxylic acids and their activated forms, such as N-hydroxyphthalimide esters (NHP esters), alkyl diacyl peroxides, alkyl peresters, and aryliodine(III) dicarboxylates. The scope and limitation of these transformations will be discussed, highlighting gaps in knowledge and research and examining the mechanisms underlying radical decarboxylation. We aim to make this review a stepping stone for further development in this field.1 Introduction2 Aliphatic Carboxylic Acids3 N-Hydroxyphthalimide Esters (NHP Esters)4 Alkyl Diacyl Peroxides5 Alkyl Peresters6 Aryliodine(III) Dicarboxylates7 Conclusion

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