scholarly journals A Mechanistic Analysis of Trimethylanilinium Salt Degradation: Implications for Methylation and Cross-coupling Applications

2021 ◽  
Author(s):  
Jack B. Washington ◽  
Michele Assante ◽  
Chunhui Yan ◽  
David McKinney ◽  
Vanessa Juba ◽  
...  
Keyword(s):  
Methyl Iodide ◽  
Phase Transfer ◽  
Cross Coupling ◽  
Closed Shell ◽  
Dual Reactivity ◽  
Aryl Group ◽  
H Nmr ◽  
Mechanistic Analysis ◽  
Degradation Analysis ◽  
Physical And Chemical

<i>N,N,N</i>-trimethylanilinium salts are known to display dual reactivity through both the aryl group and the <i>N</i>-methyl groups. These salts have thus been widely applied in cross-coupling, aryl etherification, fluorine radiolabelling, phase-transfer catalysis, supramolecular recognition, polymer design, and (more recently) methylation. However, their application as electrophilic methylating reagents remains somewhat underexplored, and an understanding of their arylation versus methylation reactivities is lacking. This study presents a mechanistic degradation analysis of <i>N,N,N</i>-trimethylanilinium salts and highlights the implications for synthetic applications of this important class of salts. Kinetic degradation studies, in both solid state and solution phases, have delivered insights into the physical and chemical parameters affecting anilinium salt stability. <sup>1</sup>H NMR kinetic analysis of salt degradation has evidenced thermal degradation to methyl iodide and the parent aniline, consistent with a closed-shell S<sub>N</sub>2-centred degradative pathway, and methyl iodide being the key reactive species in applied methylation procedures. Furthermore, the effect of halide and non-nucleophilic counterions on salt degradation has been investigated, along with deuterium isotope and solvent effects. Finally, new mechanistic insights have enabled the investigation of the use of trimethylanilinium salts in O-methylation and in improved cross-coupling strategies.

scholarly journals A Mechanistic Analysis of Trimethylanilinium Salt Degradation: Implications for Methylation and Cross-coupling Applications

2021 ◽  
Author(s):  
Jack B. Washington ◽  
Michele Assante ◽  
Chunhui Yan ◽  
David McKinney ◽  
Vanessa Juba ◽  
...  
Keyword(s):  
Methyl Iodide ◽  
Phase Transfer ◽  
Cross Coupling ◽  
Closed Shell ◽  
Dual Reactivity ◽  
Aryl Group ◽  
H Nmr ◽  
Mechanistic Analysis ◽  
Degradation Analysis ◽  
Physical And Chemical

<i>N,N,N</i>-trimethylanilinium salts are known to display dual reactivity through both the aryl group and the <i>N</i>-methyl groups. These salts have thus been widely applied in cross-coupling, aryl etherification, fluorine radiolabelling, phase-transfer catalysis, supramolecular recognition, polymer design, and (more recently) methylation. However, their application as electrophilic methylating reagents remains somewhat underexplored, and an understanding of their arylation versus methylation reactivities is lacking. This study presents a mechanistic degradation analysis of <i>N,N,N</i>-trimethylanilinium salts and highlights the implications for synthetic applications of this important class of salts. Kinetic degradation studies, in both solid state and solution phases, have delivered insights into the physical and chemical parameters affecting anilinium salt stability. <sup>1</sup>H NMR kinetic analysis of salt degradation has evidenced thermal degradation to methyl iodide and the parent aniline, consistent with a closed-shell S<sub>N</sub>2-centred degradative pathway, and methyl iodide being the key reactive species in applied methylation procedures. Furthermore, the effect of halide and non-nucleophilic counterions on salt degradation has been investigated, along with deuterium isotope and solvent effects. Finally, new mechanistic insights have enabled the investigation of the use of trimethylanilinium salts in O-methylation and in improved cross-coupling strategies.

scholarly journals Trialkylammonium Salt Degradation: Implications for Methylation and Cross-coupling

2021 ◽  
Author(s):  
Jack Brandon Washington ◽  
Michele Assante ◽  
Chunhui Yan ◽  
David R McKinney ◽  
Vanessa Juba ◽  
...  
Keyword(s):  
Cross Coupling ◽  
Methyl Groups ◽  
Dual Reactivity ◽  
Aryl Group

Trialkylammonium (most notably N,N,N-trimethylanilinium) salts are known to display dual reactivity through both the aryl group and the N-methyl groups. These salts have thus been widely applied in cross-coupling, aryl...

scholarly journals Pd Nanoparticles Stabilized by Hypercrosslinked Polystyrene Catalyze Selective Triple C-C Bond Hydrogenation and Suzuki Cross-Coupling

2019 ◽  
Vol 2019 ◽  
pp. 1-7 ◽  
Author(s):  
Linda Zh. Nikoshvili ◽  
Nadezhda A. Nemygina ◽  
Tatiana E. Khudyakova ◽  
Irina Yu. Tiamina ◽  
Alexey V. Bykov ◽  
...  
Keyword(s):  
Phase Transfer ◽  
Aryl Halide ◽  
Coupling Reaction ◽  
Cross Coupling ◽  
Pd Nanoparticles ◽  
Hypercrosslinked Polystyrene ◽  
Reductive Activation ◽  
Pd Nanoparticle ◽  
Cross Coupling Reaction ◽  
Precursor Decomposition

This paper describes the synthesis of Pd-containing catalysts based on nonfunctionalized hypercrosslinked polystyrene via impregnation with Pd acetate. Developed Pd nanoparticulate catalyst allowed achieving conversion of aryl halide up to 90% in Suzuki cross-coupling reaction under mild conditions and at the absence of phase-transfer agents. During the selective hydrogenation of triple C-C bond of 2-methyl-3-butyn-2-ol, up to 96% selectivity with respect to corresponding olefinic alcohol was found at 95% conversion. The influences of the procedure of catalyst synthesis like precursor decomposition and reductive activation method on Pd nanoparticle formation are discussed.

Novel lariat calix[4]-1,3-aza-crowns with two branched chains — The excellent phase transfer catalysts for nucleophilic substitution reaction

2010 ◽  
Vol 88 (7) ◽  
pp. 622-627 ◽  
Author(s):  
Fafu Yang ◽  
Yanhua Wang ◽  
Hongyu Guo ◽  
Jianwei Xie ◽  
Zhiqiang Liu
Keyword(s):  
Nucleophilic Substitution ◽  
Substitution Reaction ◽  
Phase Transfer ◽  
Hard Metal ◽  
Nucleophilic Substitution Reaction ◽  
Phenyl Isothiocyanate ◽  
Phase Transfer Catalysts ◽  
H Nmr ◽  
Branched Chains ◽  
New Compounds

By reacting calix[4]-1,3-diethoxylaminoethyl derivative (2) with phenyl isothiocyanate, novel dendritic calix[4]arene derivative (3) with two different branched chains was synthesized in a yield of 78%. By reacting compound 2 with 1,6-diisocyanatohexane or N,N′-bis(2-chloracetamide)ethylene in a “1 + 1” intermolecular addition mode, novel lariat calix[4]-1,3-aza-crowns (4 and 5, respectively) with two branched ethoxyl chains were prepared in reasonable yields. The composition, structures, and conformations of all new compounds were confirmed by elemental analyses, IR, ESI-MS, 1H NMR, and so forth. The liquid–liquid extraction experiments showed that all new hosts possessed good extraction abilities towards soft and hard metal cations. The liquid membrane transport experiments suggested that they had good transport abilities for K+ and Ag+. The experiments of phase transfer catalysis indicated that they possessed excellent catalytic properties of aromatic nucleophilic substitution reaction and benzyl nucleophilic substitution. The optimum yields of products in catalytic reaction were as high as approximately 100%.

PALLADIUM AND PHASE TRANSFER CATALYZED HECK CROSS COUPLING REACTION IN WATER UNDER MICROWAVE IRRADIATION

2002 ◽  
Vol 32 (10) ◽  
pp. 1607-1614 ◽  
Author(s):  
Jin-Xian Wang ◽  
Zhanxiang Liu ◽  
Yulai Hu ◽  
Bangguo Wei ◽  
Lin Bai
Keyword(s):  
Microwave Irradiation ◽  
Phase Transfer ◽  
Coupling Reaction ◽  
Cross Coupling ◽  
Cross Coupling Reaction ◽  
Reaction In Water

Sila-Pharmaka, 9. Mitt. [1] Darstellung und Eigenschaften potentiell curarewirksamer Silicium-Verbindungen, I / Sila-Drugs, 9th Communication [1] Preparation and Properties of Silicon Compounds with Potential Curare-Like Activity, I

1978 ◽  
Vol 33 (4) ◽  
pp. 412-416 ◽  
Author(s):  
Reinhold Tacke ◽  
Roland Niedner
Keyword(s):  
Mass Spectroscopy ◽  
Chemical Properties ◽  
Physical And Chemical Properties ◽  
Organosilicon Compounds ◽  
Silicon Compounds ◽  
H Nmr ◽  
Toxicological Data ◽  
Physical And Chemical ◽  
First Time ◽  
And Chemical Properties

Abstract Organosilicon compounds 8, 9 and 10 with potential curare-like action and their precursors 5, 6 and 7 were synthesized for the first time. 5−10 were characterized by their physical and chemical properties, and their structures were confirmed by analyses, 1 H NMR and mass spectroscopy (only for 5−7). The pharmacological and toxicological data of 8, 9 and 10 are reported.

Synthese und Eigenschaften von Alkyloxi-und Aryloxi-substituierten Trithiadiborolanen / Synthesis and Properties of Alkoxi and Aryloxi Substituted Trithiadiborolanes

1981 ◽  
Vol 36 (11) ◽  
pp. 1444-1450 ◽  
Author(s):  
Max Schmidt ◽  
Erich Sametschek
Keyword(s):  
Thermal Stability ◽  
Nmr Spectra ◽  
Chemical Properties ◽  
Physical And Chemical Properties ◽  
H Nmr ◽  
New Compounds ◽  
Physical And Chemical ◽  
Thermal Stability Of ◽  
And Chemical Properties

Abstract The first examples of the hitherto unknown 1,2,4-Trithia-3,5-diborolanes with B-O-C-bonds have been synthesized and characterised. The diiodo substituted ring (2) reacts with 2,6-dimethylphenol, to form 3,5-bis-(2,6-dimethylphenyloxi)-1,2,4-trithia-3,5-di-borolane (3) and HI. 3,5-Diethoxi-1,2,4-trithia-3,5-diborolane, 5, and C2H5I are formed via the cleavage of diethylether by 2. From 2 and diisopropylether, the corresponding 3,5-diisopropyloxi-1,2,4-trithia-3,5-diborolane (6) is formed. The unsymmetrical ethers methyl-t-butylether and methylphenylether undergo reactions with 2 resulting in the formation of 3,5-dimethyloxi-1,2,4-trithia-3,5-diborolane (8) (besides t-C4H9I) and 3,5-diphenyloxi-1,2,4-trithia-3,5-diborolane (10) (besides CH3I). The thermal stability of the new compounds is increasing with increasing size of R in the -OR group and from aliphatic to aromatic R in this group. IR, Raman, 1H NMR and 11B NMR spectra of the compounds are reported as well as some physical and chemical properties.

scholarly journals N,N'-(Hexane-1,6-diyl)bis(4-methyl-N-(oxiran-2-ylmethyl)benzenesulfonamide): Synthesis via cyclodextrin mediated N-alkylation in aqueous solution and further Prilezhaev epoxidation

2013 ◽  
Vol 9 ◽  
pp. 2834-2840 ◽  
Author(s):  
Julian Fischer ◽  
Simon Millan ◽  
Helmut Ritter
Keyword(s):  
Aqueous Solution ◽  
Allyl Bromide ◽  
Phase Transfer ◽  
2D Nmr ◽  
Phase Transfer Catalysts ◽  
H Nmr ◽  
Rheological Measurements

N-alkylation of N,N'-(hexane-1,6-diyl)bis(4-methylbenzenesulfonamide) with allyl bromide and subsequent Prilezhaev reaction with m-chloroperbenzoic acid to give N,N'-(hexane-1,6-diyl)bis(4-methyl-N-(oxiran-2-ylmethyl)benzenesulfonamide) is described. This twofold alkylation was performed in aqueous solution, whereby α-, and randomly methylated β-cyclodextrin were used as adequate phase transfer catalysts and the cyclodextrin–guest complexes were characterized by 1H NMR and 2D NMR ROESY spectroscopy. Finally, the curing properties of the diepoxide with lysine-based α-amino-ε-caprolactam were analyzed by rheological measurements.

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