Highly efficient conversion of aldehydes to carboxylic acid in the presence of platinum porphyrin sensitizers, air and sunlight

A variety of aromatic and aliphatic aldehydes were oxidized to the corresponding carboxylic acids in the presence of platinum porphyrin, sunlight and air in acetonitrile solvent under mild conditions. Nitrobenzaldehydes were found to be very efficient 1O2 scavengers that quench the formation of acids from any aldehyde in the presence of free-base porphyrin sensitizers. However, nitrobenzaldehydes were converted to the corresponding acids in the presence of platinum porphyrins. The platinum porphyrins are very good and efficient catalysts for a wide range of applications in the aerobic conversion of aldehydes to acids.

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Late-Stage β-C(sp3)–H Deuteration of Carboxylic Acids

10.26434/chemrxiv.14537865.v2 ◽

2021 ◽

Author(s):

Alexander Uttry ◽

Sourjya Mal ◽

Manuel van Gemmeren

Keyword(s):

Carboxylic Acid ◽

Carboxylic Acids ◽

Late Stage ◽

Bioactive Molecules ◽

Wide Range ◽

Catalyst Systems ◽

First Time

Carboxylic acid moieties are highly abundant in bioactive molecules. In this study we describe the late-stage β-C(sp3)–H deuteration of free carboxylic acids. Based on our finding that the C–H activation with our catalyst systems is reversible, the de-deuteration process was first optimized. The resulting conditions involve ethylenediamine-based ligands, which, amongst other positions, for the first time enables the functionalization of non-activated methylene β-C(sp3)–H bonds and can be used to achieve the desired deuteration when using a deuterated solvent. The reported method allows for the functionalization of a wide range of free carboxylic acids with diverse substitution patterns, as well as the late-stage deuteration of bioactive molecules and related frameworks.

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Synergetic combination of a mesoporous polymeric acid and a base enables highly efficient heterogeneous catalytic one-pot conversion of crude Jatropha oil into biodiesel

Green Chemistry ◽

10.1039/c9gc04135d ◽

2020 ◽

Vol 22 (5) ◽

pp. 1698-1709 ◽

Cited By ~ 3

Author(s):

Hu Pan ◽

Yanan Liu ◽

Qineng Xia ◽

Heng Zhang ◽

Li Guo ◽

...

Keyword(s):

Catalytic System ◽

Jatropha Oil ◽

One Pot ◽

Heterogeneous Catalytic ◽

Mild Conditions ◽

Efficient Conversion ◽

Highly Efficient ◽

Polymeric Acid

Highly efficient conversion of crude Jatropha oil to biodiesel was realized under mild conditions via a synergistic catalytic system consisting of acid (MICPHPW) and base (MICPOH) catalysts using a ‘one-pot, two-step’ strategy.

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Ce/MgAl mixed oxides derived from hydrotalcite LDH precursors as highly efficient catalysts for ketonization of carboxylic acid

Catalysis Science & Technology ◽

10.1039/c9cy01323g ◽

2019 ◽

Vol 9 (22) ◽

pp. 6335-6344 ◽

Cited By ~ 2

Author(s):

Binbo Jiang ◽

Zhixiang Xi ◽

Feipeng Lu ◽

Zhengliang Huang ◽

Yao Yang ◽

...

Keyword(s):

Carboxylic Acid ◽

Carboxylic Acids ◽

Mixed Oxides ◽

Biomass Feedstocks ◽

Highly Efficient

Ketonization of carboxylic acids provides an attractive way for upgrading biomass feedstocks into biofuels.

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SN2-Type Glycosylation with Unprotected Pyranoses

10.26434/chemrxiv.11276384.v1 ◽

2019 ◽

Author(s):

Hironori Takeuchi ◽

Yusuke Fujimori ◽

Hiromitsu Shibayama ◽

Masaru Nagaishi ◽

Yoshihiro Ueda ◽

...

Keyword(s):

Carboxylic Acid ◽

Antitumor Activity ◽

Benzoic Acid ◽

Total Synthesis ◽

Carboxylic Acids ◽

Stereoselective Glycosylation ◽

Wide Range ◽

High Stereoselectivity ◽

Glycosyl Donors

An SN2 mechanism was proposed for highly stereoselective glycosylation of benzoic acid with unprotected α-D-glucose under Mitsunobu conditions in dioxane, while an SN1 mechanism seems to be responsible for non-stereoselective glycosylation in DMF. The SN2-type glycosylation can be applicable to various unprotected pyranoses as glycosyl donors and a wide range of carboxylic acids, phenols, and imides as glycosyl acceptors, retaining its high stereoselectivity (34 examples). Glycosylation of a carboxylic acid with unprotected α-D-mannose proceeded also in an SN2 manner to directly afford a usually less accessible 1,2-cis-mannoside. An extremely short-step total synthesis of a middle molecule (1874 Da) natural glycoside with antitumor activity, coriariin A, was achieved via a double SN2 glycosylation strategy with two molecules of unprotected α-D-glucose.

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Brønsted Acid-Catalysed Allylic Amination of 1-(2-Aminoaryl)prop-2-en-1-ols to 1,2-Dihydroquinolines

Australian Journal of Chemistry ◽

10.1071/ch18191 ◽

2018 ◽

Vol 71 (9) ◽

pp. 673 ◽

Cited By ~ 1

Author(s):

David Philip Day ◽

Stuart Adam Henry ◽

Yichao Zhao ◽

Jianwen Jin ◽

Guy James Clarkson ◽

...

Keyword(s):

Room Temperature ◽

Trifluoromethanesulfonic Acid ◽

Catalyst Loading ◽

Synthetic Method ◽

Bronsted Acid ◽

Allylic Amination ◽

Mild Conditions ◽

Highly Efficient ◽

Brönsted Acid ◽

Wide Range

A highly efficient synthetic method to prepare 1,2-dihydroquinolines that relies on trifluoromethanesulfonic acid (TfOH)-catalysed allylic amination of 1-(2-aminoaryl)prop-2-en-1-ols is described. Achieved at a catalyst loading of 0.01 mol-% under mild conditions at room temperature, the reaction was found to be robust, with a wide range of substitution patterns tolerated. The corresponding N-heterocyclic adducts were obtained in good to excellent yields of 45–93 %.

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Synthesis of γ-Oxo-α-amino Acids via Radical Acylation with Carboxylic Acids

10.26434/chemrxiv.13194920 ◽

2020 ◽

Author(s):

Kay Merkens ◽

Francisco José Aguilar Troyano ◽

Khadijah Anwar ◽

Adrián Gómez Suárez

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Carboxylic Acids ◽

Functional Groups ◽

Photoredox Catalysis ◽

Average Yield ◽

Highly Efficient ◽

Wide Range ◽

Acyl Radicals

Herein we present a highly efficient, light-mediated, deoxygenative protocol to access g-oxo-a-amino acid derivatives.This radical methodology employs photoredox catalysis, in combination with triphenylphosphine, to generate acyl radicals from readily available (hetero)aromatic and vinylic carboxylic acids. This approach allows for the straightforward synthesis of g-oxo-aamino acids bearing a wide range of functional groups (e.g. Cl, CN, furan, thiophene, Bpin) in synthetically useful yields (~ 60% average yield). To further highlight the utility of the methodology, several deprotection and derivatization reactions were carried out.

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Synthesis of γ-Oxo-α-amino Acids via Radical Acylation with Carboxylic Acids

10.26434/chemrxiv.13194920.v1 ◽

2020 ◽

Author(s):

Kay Merkens ◽

Francisco José Aguilar Troyano ◽

Khadijah Anwar ◽

Adrián Gómez Suárez

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Carboxylic Acids ◽

Functional Groups ◽

Photoredox Catalysis ◽

Average Yield ◽

Highly Efficient ◽

Wide Range ◽

Acyl Radicals

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Silver-Promoted Regioselective Oxidative Decarboxylative C–H Alkylation of Phenanthridines with Carboxylic Acids

Synthesis ◽

10.1055/s-0039-1690220 ◽

2019 ◽

Vol 52 (02) ◽

pp. 239-245

Author(s):

Tianyin Huang ◽

Yang Yu ◽

Hui Wang ◽

Yifan Lin ◽

Yurui Ma ◽

...

Keyword(s):

Carboxylic Acid ◽

Carboxylic Acids ◽

Efficient Synthesis ◽

One Pot ◽

Mild Conditions ◽

One Pot Synthesis ◽

The Given

A novel oxidative decarboxylative C–H alkylation of phenanthridines with carboxylic acids was developed for the efficient synthesis of multi-substituted phenanthridine derivatives. The given method features easy availability of starting materials, high regioselectivity, and mild conditions. Furthermore, a one-pot synthesis of multi-substituted phenanthridine derivatives was realized by the reaction of biphenyl isocyanides and carboxylic acid.

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Visible-Light-Triggered Decarboxylative Alkylation of 8-Acylaminoquinoline with N-Hydroxyphthalimide Ester

Synlett ◽

10.1055/s-0039-1691579 ◽

2020 ◽

Vol 31 (07) ◽

pp. 677-682 ◽

Cited By ~ 1

Author(s):

Bin Sun ◽

Deyu Li ◽

Xiaohui Zhuang ◽

Rui Zhu ◽

Aertuke Aisha ◽

...

Keyword(s):

Visible Light ◽

Functional Groups ◽

Efficient Approach ◽

Radical Coupling ◽

Mild Conditions ◽

Highly Efficient ◽

Wide Range ◽

Reaction Proceeds ◽

Operational Simplicity

A facile protocol for visible-light-induced decarboxylative radical coupling of NHP esters with 8-aminoquinoline amides is reported, affording a highly efficient approach to synthesize a variety of 2-alkylated or 2,4-dialkylated 8-aminoquinoline derivatives. The reaction proceeds smoothly without adding any ligand, and provides the corresponding products containing a wide range of functional groups in moderate to excellent yields. This reaction uses readily available starting materials, and proceeds under mild conditions and with operational simplicity.

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