scholarly journals MOFs based on 1D structural sub-domains with Brønsted acid and redox active sites as effective bi-functional catalysts

2020 ◽  
Vol 10 (11) ◽  
pp. 3572-3585 ◽  
Author(s):  
José María Moreno ◽  
Alexandra Velty ◽  
Urbano Díaz
Keyword(s):  
Active Sites ◽  
Bronsted Acid ◽  
Brønsted Acid ◽  
One Pot ◽  
Redox Active ◽  
Brönsted Acid ◽  
Low Dimensional

Low-dimensional MOF-type catalysts containing Brønsted acid and redox active sites, based on assembled 1D organic–inorganic nanoribbons, for one-pot two-step reactions.

scholarly journals On the Role of Protonic Acid Sites in Cu Loaded FAU31 Zeolite as a Catalyst for the Catalytic Transformation of Furfural to Furan

Molecules ◽  
2021 ◽  
Vol 26 (7) ◽  
pp. 2015
Author(s):  
Łukasz Kuterasiński ◽  
Małgorzata Smoliło-Utrata ◽  
Joanna Kaim ◽  
Wojciech Rojek ◽  
Jerzy Podobiński ◽  
...  
Keyword(s):  
Active Sites ◽  
Acid Sites ◽  
Bronsted Acid ◽  
Brønsted Acid ◽  
Brønsted Acid Sites ◽  
Protonic Acid ◽  
Brönsted Acid ◽  
Brönsted Acid Sites ◽  
Bronsted Acid Sites

The aim of the present paper is to study the speciation and the role of different active site types (copper species and Brønsted acid sites) in the direct synthesis of furan from furfural catalyzed by copper-exchanged FAU31 zeolite. Four series of samples were prepared by using different conditions of post-synthesis treatment, which exhibit none, one or two types of active sites. The catalysts were characterized by XRD, low-temperature sorption of nitrogen, SEM, H2-TPR, NMR and by means of IR spectroscopy with ammonia and CO sorption as probe molecules to assess the types of active sites. All catalyst underwent catalytic tests. The performed experiments allowed to propose the relation between the kind of active centers (Cu or Brønsted acid sites) and the type of detected products (2-metylfuran and furan) obtained in the studied reaction. It was found that the production of 2-methylfuran (in trace amounts) is determined by the presence of the redox-type centers, while the protonic acid sites are mainly responsible for the furan production and catalytic activity in the whole temperature range. All studied catalysts revealed very high susceptibility to coking due to polymerization of furfural.

scholarly journals Brønsted acid-catalyzed metal-free one-pot synthesis of benzimidazoles via [4+1] heteroannulation of ortho-phenylenediamines with β-oxodithioesters

ARKIVOC ◽  
2017 ◽  
Vol 2018 (2) ◽  
pp. 81-89
Author(s):  
Abhijeet Srivastava ◽  
Gaurav Shukla ◽  
Dhananjay Yadav ◽  
Maya Shankar Singh
Keyword(s):  
Bronsted Acid ◽  
Brønsted Acid ◽  
One Pot ◽  
Metal Free ◽  
One Pot Synthesis ◽  
Brönsted Acid ◽  
Acid Catalyzed

Facile synthesis of chiral indolines through asymmetric hydrogenation of in situ generated indoles

2018 ◽  
Vol 5 (19) ◽  
pp. 2805-2809 ◽  
Author(s):  
Chang-Bin Yu ◽  
Jie Wang ◽  
Yong-Gui Zhou
Keyword(s):  
Asymmetric Hydrogenation ◽  
Hydrogenation Process ◽  
Bronsted Acid ◽  
Brønsted Acid ◽  
Facile Synthesis ◽  
One Pot ◽  
Brönsted Acid ◽  
Palladium Catalyzed ◽  
Intramolecular Condensation

A concise synthesis of chiral indolines has been developed through intramolecular condensation, deprotection and palladium-catalyzed asymmetric hydrogenation in a one-pot process with up to 96% ee. A strong Brønsted acid played an important role in both the formation of indoles and asymmetric hydrogenation process.

scholarly journals One-Pot Synthesis of 5-Hydroxymethylfurfural from Glucose by Brønsted Acid-Free Bifunctional Porous Coordination Polymers in Water

ACS Omega ◽  
2019 ◽  
Vol 4 (5) ◽  
pp. 9316-9323 ◽  
Author(s):  
Fengbing Liang ◽  
Dawei Chen ◽  
Huizhou Liu ◽  
Weimin Liu ◽  
Mo Xian ◽  
...  
Keyword(s):  
Coordination Polymers ◽  
Bronsted Acid ◽  
Brønsted Acid ◽  
Porous Coordination Polymers ◽  
One Pot ◽  
One Pot Synthesis ◽  
Brönsted Acid

scholarly journals Tartaric Acid–Zinc Nitrate as an Efficient Brønsted Acid-Assisted Lewis Acid Catalyst for the Mannich Reaction

2018 ◽  
Vol 42 (9) ◽  
pp. 463-466 ◽  
Author(s):  
Hao Dong ◽  
Qing Liu ◽  
Yuanyu Tian ◽  
Yingyun Qiao
Keyword(s):  
Tartaric Acid ◽  
Lewis Acid ◽  
Mannich Reaction ◽  
Reaction Times ◽  
Acid Catalyst ◽  
Zinc Nitrate ◽  
Bronsted Acid ◽  
Brønsted Acid ◽  
One Pot ◽  
Brönsted Acid

Tartaric acid–zinc nitrate has been found to be an efficient Brønsted acid-assisted Lewis acid catalytic system for the facile synthesis of β-amino carbonyl compounds through the one-pot Mannich reaction of aldehydes, aromatic amines and ketones in ethanol at room temperature. Remarkable enhancement of reactivity by tartaric acid (Brønsted acid) was observed in these reactions in the presence of anhydrous zinc nitrate (Lewis acid), due to coordination of the tartaric acid ligand to zinc ions increasing the acidity of the system. This procedure shows some advantages such as mild reaction conditions, short reaction times and high yields.

One-Pot Hydroxy Group Activation/Carbon-Carbon Bond Forming Sequence Using a Brønsted Base/Brønsted Acid System

2010 ◽  
Vol 352 (17) ◽  
pp. 2881-2886 ◽  
Author(s):  
Alice Devineau ◽  
Guillaume Pousse ◽  
Catherine Taillier ◽  
Jérôme Blanchet ◽  
Jacques Rouden ◽  
...  
Keyword(s):  
Hydroxy Group ◽  
Bronsted Acid ◽  
Acid System ◽  
Brønsted Acid ◽  
One Pot ◽  
Carbon Bond ◽  
Bond Forming ◽  
Carbon Carbon Bond ◽  
Brönsted Acid ◽  
Brønsted Base

Synthesis of 1-Alkyl-3-(2-oxo-2-aryl/alkyl-ethyl)indolin-2-ones through Gold/Brønsted Acid Relay Actions: Observation of Selective C=C Bond Cleavage of Enaminones

Synthesis ◽  
2017 ◽  
Vol 49 (16) ◽  
pp. 3609-3618 ◽  
Author(s):  
Yanzhong Li ◽  
Yulei Zhao ◽  
Yang Yuan ◽  
Lingkai Kong ◽  
Fangfang Zhang
Keyword(s):  
Reaction Mechanism ◽  
Bond Cleavage ◽  
Bronsted Acid ◽  
Brønsted Acid ◽  
Reaction Conditions ◽  
One Pot ◽  
Esi Ms ◽  
Ms Analysis ◽  
Brönsted Acid

A novel gold(I)/Brønsted acid sequential catalyzed/promoted procedure to synthesize 1-alkyl-3-(2-oxo-2-aryl/alkyl-ethyl)indolin-2-ones under mild reaction conditions is developed. This methodology is realized by relay actions of gold and a Brønsted acid in a one-pot multistep manner. The gold(I)-catalyzed chemoselective C(sp2)-H functionalization of enaminones and Brønsted acid promoted cleavage of the C=C bond are integrated effectively. Based on the results of control experiments and ESI-MS analysis, a possible reaction mechanism is proposed.

Aminoxylation of Thioalkynes through Radical-Polar Crossover

Synlett ◽  
2019 ◽  
Vol 31 (06) ◽  
pp. 592-594
Author(s):  
Giovanni Di Mauro ◽  
Martina Drescher ◽  
Sara Tkaczyk ◽  
Nuno Maulide
Keyword(s):  
Bronsted Acid ◽  
Brønsted Acid ◽  
Reaction Conditions ◽  
One Pot ◽  
Brönsted Acid ◽  
Direct Formation

A one-pot procedure for the aminoxylation of thioalkynes for the direct formation of α-functionalized thioesters under mild reaction conditions is reported. A ketenethionium ion is the key intermediate, which is generated in situ by Brønsted acid mediated protonation and undergoes a radical-polar crossover.

One-Pot Synthesis of 1-Substituted 1H-Isochromenes by Combining Brønsted Acid with Silver Catalysis

Synthesis ◽  
2016 ◽  
Vol 49 (06) ◽  
pp. 1243-1254 ◽  
Author(s):  
Dieter Enders ◽  
Nina Bröhl ◽  
Dipti Kundu ◽  
Gerhard Raabe
Keyword(s):  
Bronsted Acid ◽  
Brønsted Acid ◽  
One Pot ◽  
One Pot Synthesis ◽  
Silver Catalysis ◽  
Brönsted Acid

Efficient synthesis of pyrrolo[1,2-a]quinoxalines catalyzed by a Brønsted acid through cleavage of C–C bonds

2016 ◽  
Vol 14 (36) ◽  
pp. 8529-8535 ◽  
Author(s):  
Caixia Xie ◽  
Lei Feng ◽  
Wanli Li ◽  
Xiaojun Ma ◽  
Xinkun Ma ◽  
...  
Keyword(s):  
Direct Synthesis ◽  
Domino Reaction ◽  
Bronsted Acid ◽  
Brønsted Acid ◽  
Efficient Synthesis ◽  
One Pot ◽  
Keto Esters ◽  
Brönsted Acid

An efficient and convenient one-pot domino reaction for the direct synthesis of pyrrolo[1,2-a]quinoxalines has been developed. β-Diketones and β-keto esters are well tolerated to give the corresponding products in moderate to excellent yields.

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