Synthesis and Applications of Chiral Bicyclic Bisborane Catalysts

Synthesis ◽  
2021 ◽  
Author(s):  
Zhao-Ying Yang ◽  
Ming Zhang ◽  
Xiao-Chen Wang
Keyword(s):  
Transition Metal ◽  
Lewis Acid ◽  
Asymmetric Hydrogenation ◽  
Acid Catalysts ◽  
Frustrated Lewis Pairs ◽  
Lewis Acid Catalysts ◽  
Lewis Bases ◽  
Metal Free ◽  
Hydrogenation Reactions ◽  
Acid Catalyzed

The development of chiral borane Lewis acid catalysts opened the door for transition-metal-free catalyzed asymmetric organic reactions. Herein, we have summarized our work on the preparation of two classes of novel chiral bicyclic bisborane Lewis acid catalysts derived from C2-symmetric [3.3.0] dienes and [4.4] dienes, respectively. These catalysts not only form frustrated Lewis pairs with Lewis bases to catalyze asymmetric hydrogenation reactions but also activate Lewis basic functional groups in traditional Lewis acid catalyzed asymmetric reactions.

scholarly journals Synthesis of 3,3′-Disubstituted Indolenines Utilizing the Lewis Acid Catalyzed Alkylation of 2,3-Disubstituted Indoles with Trichloroacetimidates

Synlett ◽  
2017 ◽  
Vol 28 (17) ◽  
pp. 2335-2339 ◽  
Author(s):  
John Chisholm ◽  
Arijit Adhikari ◽  
Léa Radal
Keyword(s):  
Transition Metal ◽  
Lewis Acid ◽  
Acid Catalysts ◽  
Lewis Acid Catalysts ◽  
Reaction Conditions ◽  
Complex Molecules ◽  
Synthetic Intermediates ◽  
Acid Catalyzed ◽  
Metal Catalyzed ◽  
Effective Reaction

Trichloroacetimidates function as effective electrophiles for the selective C3-alkylation of 2,3-disubstituted indoles to provide 3,3′-disubstituted indolenines. These indolenines are common synthetic intermediates that are often utilized in the synthesis of complex molecules. Effective reaction conditions utilizing Lewis acid catalysts have been determined, and the scope of the reaction with respect to indole and imidate reaction partner has been investigated. This chemistry provides an alternative to base promoted and transition-metal-catalyzed methods that are more commonly utilized to access similar indolenines.

Development of silica-supported frustrated Lewis pairs: highly active transition metal-free catalysts for the Z-selective reduction of alkynes

2016 ◽  
Vol 6 (3) ◽  
pp. 882-889 ◽  
Author(s):  
Kai C. Szeto ◽  
Wissam Sahyoun ◽  
Nicolas Merle ◽  
Jessica Llop Castelbou ◽  
Nicolas Popoff ◽  
...  
Keyword(s):  
Transition Metal ◽  
Lewis Acid ◽  
Selective Reduction ◽  
Frustrated Lewis Pairs ◽  
Acid Base ◽  
Metal Free ◽  
Highly Active ◽  
Active Transition ◽  
Lewis Pairs

Supported Lewis acid/base systems based have been prepared and characterized.

scholarly journals Double metal cyanides as heterogeneous Lewis acid catalysts for nitrile synthesis via acid-nitrile exchange reactions

2019 ◽  
Vol 55 (86) ◽  
pp. 12984-12987
Author(s):  
Carlos Marquez ◽  
Matthieu Corbet ◽  
Simon Smolders ◽  
Philippe Marion ◽  
Dirk De Vos
Keyword(s):  
Transition Metal ◽  
Exchange Reaction ◽  
Lewis Acid ◽  
Acid Catalysts ◽  
Exchange Reactions ◽  
Lewis Acid Catalysts ◽  
Metal Cyanides ◽  
Acid Nitrile

A series of transition metal-based double metal cyanides (DMCs) were studied as catalysts for the synthesis of nitriles via acid-nitrile exchange reaction.

scholarly journals Electrophilic bis-fluorophosphonium dications: Lewis acid catalysts from diphosphines

2015 ◽  
Vol 6 (3) ◽  
pp. 2016-2021 ◽  
Author(s):  
Michael H. Holthausen ◽  
Rashi R. Hiranandani ◽  
Douglas W. Stephan
Keyword(s):  
Lewis Acid ◽  
Lewis Acidity ◽  
Spatial Proximity ◽  
Acid Catalysts ◽  
Lewis Acid Catalysts ◽  
Acid Catalyzed

A series of electrophilic bis-fluorophosphonium dications dervied from diphosphines with naphthalene- and (oligo)methylene-linkers is presented. The resulting Lewis acidity is demonstrated to depend on the spatial proximity between the P moieties as evidenced in several Lewis acid catalyzed transformations.

Metal-Free Living Cationic Polymerization Using Diaryliodonium Salts as Organic Lewis Acid Catalysts

2020 ◽  
Vol 53 (11) ◽  
pp. 4185-4192
Author(s):  
Rui Haraguchi ◽  
Tsuyoshi Nishikawa ◽  
Arihiro Kanazawa ◽  
Sadahito Aoshima
Keyword(s):  
Lewis Acid ◽  
Cationic Polymerization ◽  
Acid Catalysts ◽  
Lewis Acid Catalysts ◽  
Free Living ◽  
Metal Free ◽  
Living Cationic Polymerization ◽  
Diaryliodonium Salts

Friedel–Crafts Chemistry. Part 48. Concise Synthesis of Condensed Azaheterocyclic [1,8]naphthyridinones, Azepino-, Azocino-, and Azoninoquinoline Systems via Friedel–Crafts Ring Closures

2017 ◽  
Vol 70 (10) ◽  
pp. 1082 ◽  
Author(s):  
Hassan A. K. Abd El-Aal
Keyword(s):  
Lewis Acid ◽  
Acid Catalysts ◽  
Lewis Acid Catalysts ◽  
Acid Catalyzed ◽  
Keto Analogues ◽  
Brønsted And Lewis Acid

Unprecedented construction of a novel series of quinoline heteropolycycles (tetracyclic keto-analogues of [1,8]naphthyridinones, azepino-, azocino- and azonino[2,3-b]quinolinones systems) 10a–i by Friedel–Crafts cycliacylation reactions is described. Starting heterocyclic acids precursors 3a–i were prepared from easily accessible 2-chloroquinoline-3-carbaldehyde 1 via a three different synthetic pathways. Acid-catalyzed ring closures of the resulting tosylated acids were achieved under the influence of both Brønsted and Lewis acid catalysts. The present strategy enables a straightforward synthesis to fused tetracyclic quinolinone skeletons as demonstrated by concise and atom-economical syntheses.

scholarly journals Recent Advances in the Brønsted/Lewis Acid Catalyzed Conversion of Glucose to HMF and Lactic Acid: Pathways toward Bio-Based Plastics

Catalysts ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1395
Author(s):  
Cristina Megías-Sayago ◽  
Sara Navarro-Jaén ◽  
Fabien Drault ◽  
Svetlana Ivanova
Keyword(s):  
Lactic Acid ◽  
Lewis Acid ◽  
Catalyst Design ◽  
Added Value ◽  
Present Review ◽  
Acid Catalysts ◽  
Lewis Acid Catalysts ◽  
Starting Point ◽  
Acid Catalyzed ◽  
Multifunctional Catalyst

One of the most trending topics in catalysis recently is the use of renewable sources and/or non-waste technologies to generate products with high added value. That is why, the present review resumes the advances in catalyst design for biomass chemical valorization. The variety of involved reactions and functionality of obtained molecules requires the use of multifunctional catalyst able to increase the efficiency and selectivity of the selected process. The use of glucose as platform molecule is proposed here and its use as starting point for biobased plastics production is revised with special attention paid to the proposed tandem Bronsted/Lewis acid catalysts.

Metal-free pincer ligand chemistry polycationic phosphonium Lewis acids

2017 ◽  
Vol 46 (12) ◽  
pp. 3921-3928 ◽  
Author(s):  
Kevin M. Szkop ◽  
Douglas W. Stephan
Keyword(s):  
Lewis Acid ◽  
Lewis Acids ◽  
Acid Catalysts ◽  
Phosphonium Salts ◽  
Lewis Acid Catalysts ◽  
Pincer Ligand ◽  
Metal Free ◽  
Methyl Pyridine

Oxidation with or without subsequent methylation of the pyridine of 2,6-bis(diphenylphosphine)methyl pyridine affords di- and tricationic phosphonium salts. These species are used as Lewis acid catalysts for the dimerization of 1,1-diphenylethylene, the hydrodefluorination of 1-fluoroadamantane, and the dehydrocoupling of phenol and silane.

Sign in / Sign up

Export Citation Format

Share Document