THE ALKYLATION OF PRIMARY AMINES WITH ALUMINUM ALKOXIDES TO GIVE SECONDARY AMINES FREE FROM TERTIARY AMINES

1924 ◽  
Vol 46 (3) ◽  
pp. 741-746 ◽  
Author(s):  
Wilbur A. Lazier ◽  
Homer Adkins
1990 ◽  
Vol 55 (4) ◽  
pp. 1077-1098 ◽  
Author(s):  
Jiří Urban ◽  
Zdeněk Šedivý ◽  
Jiří Holubek ◽  
Emil Svátek ◽  
Miroslav Ryska ◽  
...  

2-(Methoxyphenylthio)benzaldehydes Xa-Xd were reacted with nitroethane in boiling acetic acid to give the corresponding 1-aryl-2-nitropropenes XIIa-XIId; benzonitriles XIIIa and XIIIc and benzaldoximes XXIc and XXId were isolated as by-products. Chromatographed compounds XIIa-XIId were reduced with lithium aluminium hydride to the primary amines VIIa-VIId, and formylated by heating with ethyl formate to the formamides XIVa, XIVc, and XIVd. Reduction of the formamides with lithium aluminium hydride afforded the secondary amines VIIIa, VIIIc, and VIIId, and methylation of the primary amines with formic acid and formaldehyde gave the tertiary amines IXa, IXc, and IXd. Compound VIIIa was prepared also by an alternative route starting from the nitrile XIIIa and proceeding via XIXa and XIVa. Some of the methoxylated amines were demethylated either by heating with pyridine hydrochloride or by treatment with boron tribromide to the title compounds IVa, IVc, Vc, Vd, VIa, and VIc. The amines prepared were transformed to salts for characterization and for pharmacological testing. Compound VIIIa (hydrogen oxalate V⁄FB-15 475) showed clearly the character of a potential antidepressant.


2018 ◽  
Author(s):  
Diana Ainembabazi ◽  
Nan An ◽  
Jinesh Manayil ◽  
Kare Wilson ◽  
Adam Lee ◽  
...  

<div> <p>The synthesis, characterization, and activity of Pd-doped layered double hydroxides (Pd-LDHs) for for acceptorless amine dehydrogenation is reported. These multifunctional catalysts comprise Brønsted basic and Lewis acidic surface sites that stabilize Pd species in 0, 2+, and 4+ oxidation states. Pd speciation and corresponding cataytic performance is a strong function of metal loading. Excellent activity is observed for the oxidative transamination of primary amines and acceptorless dehydrogenation of secondary amines to secondary imines using a low Pd loading (0.5 mol%), without the need for oxidants. N-heterocycles, such as indoline, 1,2,3,4-tetrahydroquinoline, and piperidine, are dehydrogenated to the corresponding aromatics with high yields. The relative yields of secondary imines are proportional to the calculated free energy of reaction, while yields for oxidative amination correlate with the electrophilicity of primary imine intermediates. Reversible amine dehydrogenation and imine hydrogenation determine the relative imine:amine selectivity. Poisoning tests evidence that Pd-LDHs operate heterogeneously, with negligible metal leaching; catalysts can be regenerated by acid dissolution and re-precipitation.</p> </div> <br>


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