An Effective Synthesis of N,N-Diphenyl Carbazolium Salts

Synlett ◽  
2017 ◽  
Vol 29 (10) ◽  
pp. 1314-1318 ◽  
Author(s):  
Charles Diesendruck ◽  
Sinai Aharonovich ◽  
Nansi Gjineci ◽  
Dario Dekel
Keyword(s):  
Positive Charge ◽  
Quaternary Ammonium Salts ◽  
Simple Approach ◽  
Ammonium Salts ◽  
State Structure ◽  
Pi Systems ◽  
Effective Synthesis ◽  
Short Time ◽  
First Time ◽  
General Method

Tetraaryl ammonium salts are a synthetic challenge, since there is no general method for the arylation of triaryl amines. Contrary to other quaternary ammonium salts, tetraaryl ammonium salts should be very chemically stable. The ipso carbons are not very electrophilic, since the positive charge is distributed throughout the pi systems and they have no acidic β hydrogens. Here we demonstrate a simple approach to N,N-diphenyl carbazolium salts using only three synthetic steps, allowing for an easy production of these salts in large amounts and in a relatively short time. In addition, we study the Cu(I) catalyzed multi-arylation of 2,2’-diaminobiphenyl, focusing on the regioselectivity of each step. Finally, we characterize, for the first time, the solid state structure of a tetraaryl ammonium salt.

scholarly journals Synthetic Derivatives of Natural Alkaloid Harmine

2016 ◽  
Vol 11 (3) ◽  
pp. 199
Author(s):  
N.M. Ismagulova ◽  
Zh.S. Nurmaganbetov ◽  
A.Zh. Turmukhambetov ◽  
T.S. Seitembetov ◽  
S.M. Adekenov
Keyword(s):  
Indole Alkaloid ◽  
Quaternary Ammonium Salts ◽  
Ammonium Salts ◽  
Peganum Harmala ◽  
Underground Part ◽  
X Ray ◽  
Natural Alkaloid ◽  
First Time ◽  
Synthetic Derivatives ◽  
Derivatives Of

The indole alkaloid harmine was extracted from underground part of <em>Peganum harmala L.</em> With the purpose of obtaining the new biological active derivatives on base of alkaloid harmine the chemical modification was carried out. The p-toluolsulfochlorid, p-toluolsulfoacid, hydrochloric, sulfuric, nitric acids, dioxide selenium and phthalic anhydride have been chosen as modifiers. For the first time quaternary ammonium salts, derivatives of N-oxide and N (2)-oxyharminiumphthalate harmine are synthesized. The structure of the synthesized compounds is determined by methods of the spectral analysis and X-ray analysis. Antimicrobic and phagocytosis stimulating activities of isolated alkaloids and their derivatives are investigated.

Strategies for the Synthesis of N-Arylammonium Salts

Synthesis ◽  
2017 ◽  
Vol 49 (16) ◽  
pp. 3535-3545 ◽  
Author(s):  
Charles Diesendruck ◽  
Shlomy Arava
Keyword(s):  
Organic Chemistry ◽  
Quaternary Ammonium ◽  
Quaternary Ammonium Salts ◽  
Ammonium Salts ◽  
Tertiary Amines ◽  
Pyrylium Salts ◽  
Menshutkin Reaction ◽  
Nucleophilic Aromatic Substitutions ◽  
Ammonium Compounds ◽  
General Method

The N-arylation of tertiary amines to provide sp3 quaternary ammonium salts is a challenge in organic chemistry. To date, no general method for such arylations has been established. Here, we summarize a variety of strategies that have been tested, starting with harsh nucleophilic aromatic substitutions, through to the use of copper catalysis and the application of strong electrophiles, such as phenyl cations and benzynes. The achievements and limitations of each method are summarized, and the challenges yet to be met in the synthesis of charged ammonium compounds are described.1 Introduction2 Alkylation of Anilines: The Menshutkin Reaction3 Arylations3.1 Nucleophilic Aromatic Substitutions by Tertiary Amines3.2 Preparation of N-Arylpyridinum Salts from Zincke and Pyrylium Salts3.3 Arylations Using Phenyl Cations3.4 Copper-Catalyzed Arylation of N-Heteroarenes3.5 Benzynes as Aryl Electrophiles4 Conclusions and Perspective

scholarly journals Base-free enantioselective SN2 alkylation of 2-oxindoles via bifunctional phase-transfer catalysis

2021 ◽  
Vol 17 ◽  
pp. 2287-2294
Author(s):  
Mili Litvajova ◽  
Emiliano Sorrentino ◽  
Brendan Twamley ◽  
Stephen J Connon
Keyword(s):  
Hydrogen Bond ◽  
Ad Hoc ◽  
Phase Transfer Catalysis ◽  
Phase Transfer ◽  
Quaternary Ammonium Salts ◽  
Enantioselective Synthesis ◽  
Ammonium Salts ◽  
Synthetic Utility ◽  
First Time ◽  
Derivatives Of

N-Protected oxindole derivatives of unprecedented malleability bearing ester moieties at C-3 have been shown to participate in enantioselective phase-transfer-catalysed alkylations promoted by ad-hoc designed quaternary ammonium salts derived from quinine bearing hydrogen-bond donating substituents. For the first time in such phase-transfer-catalysed enolate alkylations, the reactions were carried out under base-free conditions. It was found that urea-based catalysts outperformed squaramide derivatives, and that the installation of a chlorine atom adjacent to the catalyst’s quinoline moiety aided in avoiding selectivity-reducing complications related to the production of HBr in these processes. The influence of steric and electronic factors from both the perspective of the nucleophile and electrophile were investigated and levels of enantiocontrol up to 90% ee obtained. The synthetic utility of the methodology was demonstrated via the concise enantioselective synthesis of a potent CRTH2 receptor antagonist.

Palladium-catalyzed carbonylation of benzylic ammonium salts to amides and esters via C–N bond activation

2018 ◽  
Vol 16 (17) ◽  
pp. 3099-3103 ◽  
Author(s):  
Weijie Yu ◽  
Shuwu Yang ◽  
Fei Xiong ◽  
Tianxiang Fan ◽  
Yan Feng ◽  
...  
Keyword(s):  
Quaternary Ammonium ◽  
Bond Activation ◽  
Bond Cleavage ◽  
Quaternary Ammonium Salts ◽  
Ammonium Salts ◽  
Carbonylation Reaction ◽  
Palladium Catalyzed ◽  
First Time ◽  
Acid Esters

An efficient palladium-catalyzed carbonylation reaction of readily available quaternary ammonium salts with CO is reported for the first time to afford arylacetamides and arylacetic acid esters via benzylic C–N bond cleavage.

Poly(arylene ether sulfone) crosslinked networks with pillar[5]arene units grafted by multiple long-chain quaternary ammonium salts for anion exchange membranes

2020 ◽  
Vol 56 (6) ◽  
pp. 928-931 ◽  
Author(s):  
Jinwu Peng ◽  
Minhui Liang ◽  
Zhenchao Liu ◽  
Peng Wang ◽  
Chengying Shi ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Anion Exchange ◽  
Quaternary Ammonium ◽  
Quaternary Ammonium Salts ◽  
Ammonium Salts ◽  
Anion Exchange Membranes ◽  
Arylene Ether ◽  
Crosslinked Networks ◽  
First Time ◽  
Long Chain

For the first time, high-molecular-weight pillar[5]arene-containing aromatic polymers were synthesized and further modified for application as anion exchange membranes.

Synthesis and stability of 1-aminoalkylphosphonic acid quaternary ammonium salts

2021 ◽  
Author(s):  
Tomasz K. Olszewski ◽  
Anna Brol
Keyword(s):  
Phosphonic Acid ◽  
Quaternary Ammonium ◽  
Alkylating Agent ◽  
Quaternary Ammonium Salts ◽  
Ammonium Salts ◽  
Aminoalkylphosphonic Acid

An effective protocol for quaternization of simple 1-aminoalkylphosphonic acids under basic conditions and using Me2SO4 as convenient alkylating agent is reported. In the course of reaction phosphonic acid quaternary ammonium...

scholarly journals Efficacy of compressed sodium chloride (CSC) against E. coli and Candida auris in minutes and methods improvement for testing

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Lan N. Truong ◽  
Brayden D. Whitlock
Keyword(s):  
Sodium Chloride ◽  
Improved Method ◽  
Candida Auris ◽  
Antimicrobial Surfaces ◽  
E Coli ◽  
Route Of Transmission ◽  
The World ◽  
Short Time ◽  
First Time ◽  
Time Point

AbstractControlling infections has become one of the biggest problems in the world, whether measured in lives lost or money spent. This is worsening as pathogens continue becoming resistant to therapeutics. Antimicrobial surfaces are one strategy being investigated in an attempt to decrease the spread of infections through the most common route of transmission: surfaces, including hands. Regulators have chosen two hours as the time point at which efficacy should be measured. The objectives of this study were to characterize the new antimicrobial surface compressed sodium chloride (CSC) so that its action may be understood at timepoints more relevant to real-time infection control, under two minutes; to develop a sensitive method to test efficacy at short time points; and to investigate antifungal properties for the first time. E. coli and Candida auris are added to surfaces, and the surfaces are monitored by contact plate, or by washing into collection vats. An improved method of testing antimicrobial efficacy is reported. Antimicrobial CSC achieves at least 99.9% reduction of E. coli in the first two minutes of contact, and at least 99% reduction of C. auris in one minute.

scholarly journals Bactericidal activity of three different antiseptic ophthalmic preparations as surgical prophylaxis

2021 ◽  
Author(s):  
Daniele Tognetto ◽  
Marco R. Pastore ◽  
Gian Marco Guerin ◽  
Giuliana Decorti ◽  
Martina Franzin ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Povidone Iodine ◽  
Bacterial Load ◽  
Viable Cells ◽  
Polyethylene Glycol 1000 ◽  
Oil Concentration ◽  
Short Time ◽  
First Time ◽  
Antiseptic Solutions

Abstract Purpose In the era of antibiotic resistance, there is an increased interest in antiseptic solutions that might represent a reliable option for ocular surface disinfection. The objective of this study is to compare for the first time three different antiseptic ophthalmic preparations to assess their in vitro antimicrobial activity. Methods The antiseptic activity of three commercial ophthalmic solutions, IODIM (povidone-iodine 0.6% in hyaluronic acid vehicle—Medivis, Catania, Italy), OZODROP (nanoemulsion with ozonated oil—concentration not specified—FBVision, Ophthalmic Pharmaceuticals, Rome, Italy), and DROPSEPT (chlorhexidine 0.02% and vitamin E 0.5% Tocopherol Polyethylene Glycol 1000 Succinate—TPGS, Sooft Italia, Montegiorgio, Italy), was tested in vitro on six reference strains by time-killing assays. Viable cells were evaluated after 1, 15, 30 min; 2, 6, and 24 h exposure by seeding 100 µl of the suspension (or appropriate dilutions) on LB agar or Sabouraud-dextrose agar. All plates were incubated at 37 °C for 24 h and evaluated by manually counting the colonies. Results IODIM solution showed a very rapid microbicidal activity: the number of viable cells for all the tested strains was under the detection limit (less than 10 CFU/ml) already after 1 min exposure, and this result was maintained at every incubation time. The rapid antimicrobial activity of povidone-iodine was not replicated when testing the other two antiseptics. Conclusions The study reports the great efficacy in reducing bacterial load in a very short time of povidone-iodine 0.6% compared with other antiseptic preparations.

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