Hydrosilylation and Mukaiyama Aldol-type Reactions of Imine and Quinoline Derivatives Catalyzed by a Mesoionic Carbene-Stabilized Borenium Ion

2021 ◽  
Author(s):  
Joshua J. Clarke ◽  
Karthik Devaraj ◽  
Brian Bestvater ◽  
Ryoto Kojima ◽  
Patrick Eisenberger ◽  
...  
Keyword(s):  
Room Temperature ◽  
Secondary Amines ◽  
Catalyst Loading ◽  
Quinoline Derivatives ◽  
Mukaiyama Aldol

Aldimines and ketimines containing electron-donating and electron-withdrawing groups can be hydrosilylated with borenium catalysts at as low as 1 mol% catalyst loading at room temperature, providing the corresponding secondary amines...

Alkene Difunctionalization Directed by Free Amines: Diamine Synthesis via Nickel-Catalyzed 1,2-Carboamination

2021 ◽  
Author(s):  
Taeho Kang ◽  
José Manuel González ◽  
Zi-Qi Li ◽  
Klement Foo ◽  
Peter Cheng ◽  
...  
Keyword(s):  
Nickel Catalyst ◽  
Room Temperature ◽  
Kinetic Studies ◽  
Fine Tuning ◽  
Secondary Amines ◽  
Protecting Group ◽  
Wide Range ◽  
Leaving Group ◽  
Primary And Secondary Amines ◽  
Reaction Proceeds

A versatile method to access differentially substituted 1,3- and 1,4-diamines via a nickel-catalyzed three-component 1,2-carboamination of alkenyl amines with aryl/alkenylboronic ester nucleophiles and N–O electrophiles is reported. The reaction proceeds efficiently with free primary and secondary amines without needing a directing auxiliary or protecting group, and is enabled by fine-tuning the leaving group on the N–O reagent. The transformation is highly regioselective and compatible with a wide range of coupling partners and alkenyl amine substrates, all performed at room temperature. A series of kinetic studies support a mechanism in which alkene coordination to the nickel catalyst is turnover-limiting.

scholarly journals Ultra-small palladium nano-particles synthesized using bulky S/Se and N donor ligands as a stabilizer: application as catalysts for Suzuki–Miyaura coupling

RSC Advances ◽  
2019 ◽  
Vol 9 (39) ◽  
pp. 22313-22319 ◽  
Author(s):  
Preeti Oswal ◽  
Aayushi Arora ◽  
Jolly Kaushal ◽  
Gyandshwar Kumar Rao ◽  
Sushil Kumar ◽  
...  
Keyword(s):  
Suzuki Coupling ◽  
Pd Nanoparticles ◽  
Nano Particles ◽  
Secondary Amines ◽  
Donor Ligands ◽  
Catalyst Loading ◽  
Aryl Chlorides ◽  
Low Catalyst Loading

Monodispersed ultrasmall Pd nanoparticles synthesized utilizing bulky organochalcogen secondary amines as stabilizers and application in Suzuki coupling of aryl chlorides at low catalyst loading.

scholarly journals Confined acids catalyze asymmetric single aldolizations of acetaldehyde enolates

Science ◽  
2018 ◽  
Vol 362 (6411) ◽  
pp. 216-219 ◽  
Author(s):  
Lucas Schreyer ◽  
Philip S. J. Kaib ◽  
Vijay N. Wakchaure ◽  
Carla Obradors ◽  
Roberta Properzi ◽  
...  
Keyword(s):  
Small Molecule ◽  
Active Site ◽  
Aldol Reaction ◽  
Catalyst Loading ◽  
Mukaiyama Aldol Reaction ◽  
Mukaiyama Aldol

Reactions that form a product with the same reactive functionality as that of one of the starting compounds frequently end in oligomerization. As a salient example, selective aldol coupling of the smallest, though arguably most useful, enolizable aldehyde, acetaldehyde, with just one partner substrate has proven to be extremely challenging. Here, we report a highly enantioselective Mukaiyama aldol reaction with the simple triethylsilyl (TES) andtert-butyldimethylsilyl (TBS) enolates of acetaldehyde and various aliphatic and aromatic acceptor aldehydes. The reaction is catalyzed by recently developed, strongly acidic imidodiphosphorimidates (IDPi), which, like enzymes, display a confined active site but, like small-molecule catalysts, have a broad substrate scope. The process is scalable, fast, efficient (0.5 to 1.5 mole % catalyst loading), and greatly simplifies access to highly valuable silylated acetaldehyde aldols.

Influence of Catalyst Loading Method on Titania-Based Optical Hydrogen Gas Sensing Properties

2013 ◽  
Vol 582 ◽  
pp. 210-213 ◽  
Author(s):  
Junichi Hamagami ◽  
Ryo Araki ◽  
Shohei Onimaru ◽  
G. Kawamura ◽  
Atsunori Matsuda
Keyword(s):  
Palladium Catalyst ◽  
Room Temperature ◽  
Gas Sensing ◽  
Hydrogen Gas ◽  
Catalyst Loading ◽  
Sensing Properties ◽  
Precise Control ◽  
Sensor Performance ◽  
Loading Method ◽  
Gas Sensing Properties

We reported that titania ceramic coating loaded with palladium catalyst worked as an optical hydrogen gas sensor at room temperature. The palladium metal of this sensor worked as a catalyst not only for room-temperature operation but also for high selectivity to hydrogen gas. Precise control of metal/ceramic interface between the titania and the palladium was very important in order to improve the sensor performance such as sensitivity, response time, recovery time. Influence of a difference in palladium-catalyst loading method (photodeposition and sputtering) on the optical hydrogen gas sensing properties for the titania-based sensor was investigated. It was found that the catalytic loading process significantly affected the optical hydrogen characteristics of the titania-based coating.

Aroylacetylene Based Amino-Yne Click Polymerization toward Nitrogen Containing Polymers

2019 ◽  
Author(s):  
Xu Chen ◽  
Rong Hu ◽  
Bo Song ◽  
Anjun Qin ◽  
Ben Zhong Tang
Keyword(s):  
Room Temperature ◽  
Aqueous System ◽  
Secondary Amines ◽  
Primary Amines ◽  
Molecular Weights ◽  
Highly Efficient ◽  
Click Polymerization ◽  
Application Prospects

A highly efficient, spontaneous, and atom-economic polymerization of aroylacetylenes and amines at room temperature in air was established, and poly(<i>β</i>-enaminone)s with high molecular weights were produced in nearly quantitative yields. Moreover, singly <i>E</i>-configuration polymers can be obtained efficiently with secondary amines, while absolute <i>Z</i>-configuration products were prepared when using primary amines. In addition, the poly(<i>β</i>-enaminone)s can be degraded by primary amines in aqueous system to obtain definite compounds, proving their wide application prospects as degradable nitrogen containing polymers.

Synthesis of bis-spiropiperidines using nano-CuFe2O4@chitosan as a robust and retrievable heterogeneous catalyst

2017 ◽  
Vol 41 (7) ◽  
pp. 416-419 ◽  
Author(s):  
Javad Safaei-Ghomi ◽  
Mohammad Rasool Lashkari ◽  
Hossein Shahbazi-Alavi
Keyword(s):  
Heterogeneous Catalyst ◽  
Aromatic Amine ◽  
Room Temperature ◽  
Barbituric Acid ◽  
Catalyst Loading ◽  
Reaction Conditions ◽  
One Pot ◽  
Wide Range ◽  
One Pot Condensation

An efficient pseudo six-component synthesis of bis-spiropiperidines is described by one-pot condensation of formaldehyde, aromatic amine and dimedone or N,N-dimethyl-barbituric acid using nano-CuFe2O4@chitosan at room temperature. This method provides several advantages including mild reaction conditions, applicability to wide range of substrates, reusability of the catalyst and little catalyst loading.

Reactions of Perimidin-4-ones and -6-ones with amines

1977 ◽  
Vol 30 (9) ◽  
pp. 2063 ◽  
Author(s):  
DW Cameron ◽  
EL Samuel
Keyword(s):  
Double Bond ◽  
Room Temperature ◽  
Significant Degree ◽  
Secondary Amines ◽  
Nucleophilic Attack ◽  
Side Chain ◽  
Amino Compounds ◽  
Primary And Secondary Amines ◽  
Benzenoid Ring

π-Deficient perimidin-4- and -6-one systems reacted readily with primary and secondary amines at room temperature. Nucleophilic attack occurred not only at the enone double bond, but also at positions 7 and 9 on the benzenoid ring. Highly coloured mono-, di- or tri-aminated derivatives were thereby obtained. A significant degree of bond fixation was indicated. Side-chain amination of 9-methyl substituents was observed, analogous to processes encountered in quinone chemistry. On continued contact with amine the products were converted partly into 9-formyl derivatives and partly into 9-amino compounds.

FeCl3·6H2O-Catalyzed Tandem Alkylation–Hydrolysis Reaction of Chain α-Oxo Ketene Dithioacetals with Alcohols: Efficient ­Synthesis of α-Alkylated β-Oxo Thioesters

Synlett ◽  
2017 ◽  
Vol 28 (14) ◽  
pp. 1828-1834 ◽  
Author(s):  
Haifeng Yu ◽  
Lijuan Zhao ◽  
Quanping Diao ◽  
Tiechun Li ◽  
Peiqiu Liao ◽  
...  
Keyword(s):  
Room Temperature ◽  
Hydrolysis Reaction ◽  
Catalyst Loading ◽  
Efficient Synthesis ◽  
Ketene Dithioacetals

A novel FeCl3·6H2O-catalyzed tandem Friedel–Crafts alkylation–hydrolysis reaction between chain α-oxo ketene dithioacetals and alcohols to afford α-alkylated β-oxo thioesters has been successfully developed. The reaction is efficient in the presence of catalyst loading as low as 30 mol% in MeCN at room temperature, and a wide variety of α-alkylated β-oxo thioesters are efficiently synthesized in good yields.

Green Synthesis of Pyrido[2,1-a]isoquinolines and Pyrido[1,2-a]quinolines by Using ZnO Nanoparticles

Synlett ◽  
2017 ◽  
Vol 29 (04) ◽  
pp. 493-496 ◽  
Author(s):  
Fatemeh Sheikholeslami-Farahani ◽  
Maryam Ghazvini ◽  
Somayeh Soleimani-Amiri ◽  
Masoomeh Salimifard ◽  
Rezvaneh Rostamian
Keyword(s):  
Green Synthesis ◽  
Zno Nanoparticles ◽  
Room Temperature ◽  
Solvent Free ◽  
Quinoline Derivatives ◽  
Zno Nps ◽  
Efficient Catalyst ◽  
Solvent Free Conditions ◽  
Acetylenic Compounds

Pyrido[2,1-a]isoquinoline and pyrido[1,2-a]quinoline derivatives have been produced in good yields by the reaction of isoquinoline or quinoline, activated acetylenic compounds, α-halo ketones, and triphenylphosphine in the presence of ZnO nanoparticles (NPs) as an efficient catalyst under solvent-free conditions at room temperature. The reaction workup is easy, and the products can be readily separated from the reaction mixture. ZnO NPs markedly improved the yield of the product. The catalyst showed significant reusable activity.

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