Asymmetric Phase-Transfer Catalysis of Homo- and Heterochiral Quaternary Ammonium Salts: Development and Application of Conformationally Flexible Chiral Phase-Transfer Catalysts.

ChemInform ◽  
2007 ◽  
Vol 38 (10) ◽  
Author(s):  
Takashi Ooi ◽  
Yukitaka Uematsu ◽  
Minoru Kameda ◽  
Keiji Maruoka
Keyword(s):  
Quaternary Ammonium ◽  
Phase Transfer Catalysis ◽  
Phase Transfer ◽  
Quaternary Ammonium Salts ◽  
Ammonium Salts ◽  
Chiral Phase ◽  
Phase Transfer Catalysts ◽  
Chiral Phase Transfer Catalysts

Highly enantioselective Michael addition reactions with new trimeric chiral phase transfer catalysts

2015 ◽  
Vol 39 (4) ◽  
pp. 3098-3104 ◽  
Author(s):  
Arockiam Jesin Beneto ◽  
Jayaraman Sivamani ◽  
Veeramanoharan Ashokkumar ◽  
Rajendiran Balasaravanan ◽  
Kumaraguru Duraimurugan ◽  
...  
Keyword(s):  
Michael Addition ◽  
Quaternary Ammonium ◽  
Phase Transfer ◽  
Quaternary Ammonium Salts ◽  
Ammonium Salts ◽  
Addition Reactions ◽  
Chiral Phase ◽  
Catalytic Activities ◽  
Phase Transfer Catalysts ◽  
Chiral Phase Transfer Catalysts

New types of mesitylene based tri-site containing asymmetric quaternary ammonium salts 9 (9a and 9b) were synthesized and their catalytic activities were studied using Michael addition reactions with various chalcones and diethylmalonate under mild basic conditions with very good yields and ee's.

Reaction of azides and enolisable aldehydes under the catalysis of organic bases and Cinchona based quaternary ammonium salts

2017 ◽  
Vol 15 (24) ◽  
pp. 5227-5235 ◽  
Author(s):  
Dario Destro ◽  
Sandra Sanchez ◽  
Mauro Cortigiani ◽  
Mauro F. A. Adamo
Keyword(s):  
Quaternary Ammonium ◽  
Phase Transfer Catalysis ◽  
Phase Transfer ◽  
Quaternary Ammonium Salts ◽  
Ammonium Salts ◽  
Chiral Phase ◽  
Organic Bases

This work describes a two-step sequence to prepare amides in moderate enantioselectivity from azides and enolisable aldehydes that proceeds under chiral phase transfer catalysis.

Esterification of 1,4-dichlorobutane with sodium formate under solid–liquid phase transfer catalysis. A kinetic study

1989 ◽  
Vol 67 (2) ◽  
pp. 245-249 ◽  
Author(s):  
Hayder A. Zahalka ◽  
Yoel Sasson
Keyword(s):  
Liquid Phase ◽  
Kinetic Study ◽  
Quaternary Ammonium ◽  
Phase Transfer Catalysis ◽  
Phase Transfer ◽  
Sodium Formate ◽  
Product Distribution ◽  
Quaternary Ammonium Salts ◽  
Ammonium Salts ◽  
Solid Liquid

Kinetic data are reported regarding the esterification of 1,4-dichlorobutane with sodium formate catalyzed by quaternary ammonium salts as a model for reactions in series, under solid–liquid phase transfer conditions. The process was found to follow a consecutive first-order mechanism of the general type A → R → S. The reactivity of the quaternary ammonium salts with regard to the counteranion was Cl− > Br− > 1− > HSO4−. The reaction rate was linearly dependent on catalyst concentration up to 12 mol% of catalyst relative to the substrate. Above this concentration the rate was constant and independent of the amount of the catalyst. The activation energy of the two consecutive steps was found to be similar (21 kcal/mol). Therefore, the product distribution (R/S) is not appreciably affected by temperature. A mechanism termed "Thin aqueous boundary layer" is suggested for nucleophilic displacement reactions under solid–liquid phase transfer conditions. Keywords: phase transfer catalysis, series reactions, kinetic study.

scholarly journals Chiral Phase-Transfer Catalysts with Hydrogen Bond: A Powerful Tool in the Asymmetric Synthesis

Catalysts ◽  
2019 ◽  
Vol 9 (3) ◽  
pp. 244 ◽  
Author(s):  
Hongyu Wang
Keyword(s):  
Organic Synthesis ◽  
Phase Transfer Catalysis ◽  
Phase Transfer ◽  
Chiral Phase ◽  
Design Synthesis ◽  
Phase Transfer Catalysts ◽  
The Past ◽  
Hydrogen Bonding Interactions ◽  
Chiral Phase Transfer Catalysts ◽  
Made In

Asymmetric phase-transfer catalysis has been widely applied into organic synthesis for efficiently creating chiral functional molecules. In the past decades, chiral phase-transfer catalysts with proton donating groups are emerging as an extremely significant strategy in the design of novel catalysts, and a large number of enantioselective reactions have been developed. In particular, the proton donating groups including phenol, amide, and (thio)-urea exhibited unique properties for cooperating with the phase-transfer catalysts, and great advances on this field have been made in the past few years. This review summarizes the seminal works on the design, synthesis, and applications of chiral phase-transfer catalysts with strong hydrogen bonding interactions.

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