Synthesis of Aryl(di)azinyl Ketones through Copper‐ and Iron‐catalyzed Oxidation of the Methylene Group of Aryl(di)azinylmethanes

Abstract

Nachhaltige Oxidationen von Aryl(di)azinylmethanen zu Aryl(di)azinylketonen gelingen mit Kupfer‐ und Eisenkatalysatoren sowie O2 als Oxidationsmittel. Die Nützlichkeit der Methode wird durch die Synthese von 6‐(4‐Methylbenzoyl)pyridin‐2‐carbaldehyd, einer Zwischenstufe bei der Herstellung des Wirkstoffs Acrivastin, illustriert.

The Effect of Dissolved Oxygen on Kinetics during Continuous Biocatalytic Oxidations

“…For instance, while oxidation reactions, which are important for synthesizing alcohols, ketones, aldehydes and acids, are widely used in industry for the production of simple commodity chemicals, they are comparatively rarely applied in pharmaceutical syntheses, because conventional catalysts are poorly selective towards complex molecules and require harsh operating conditions. [1][2][3][4][5] Consequently, biocatalytic oxidations, which are far more selective and require significantly milder operating conditions (room temperature and pressure, as well as neutral pH), are becoming increasingly attractive for industrial implementation. [6][7][8] However, since the pharmaceutical industry and its regulators are shifting in favor of continuous end-to-end manufacturing, to improve the agility and flexibility with which drugs can be supplied [9][10][11][12][13] , biocatalysis must also follow suit.…”

One‐Pot Directing Group Formation/C−H Bond Functionalization via Copper(I) and Ruthenium(II) Catalysis

“…Next, the one‐pot directing group formation/C−H bond functionalization of various substituted benzylpyridines ( 5a – 5e ) was attempted to demonstrate the feasibility of the one‐pot approach (Figure ) . In all cases full conversions were observed, and the efficiency of the methodology was governed by the second step, that is, the C−H bond functionalization step.…”

“…NMP was distilled under reduced pressure and stored over molecular sieves under an argon atmosphere. 2‐Benzylpyridines 5a–5e were prepared according to literature procedures ,. Technical grade petroleum ether (40–60 °C) and ethyl acetate were used for column chromatography.…”

Synthesis of α‐Keto‐1,2,3‐triazoles Through Copper Iodide Catalyzed Oxygenation

“…These reactions also indicated that the CuI/TBHP couple is more efficient than KI/TBHP in oxidizing benzyltriazoles. The use of FeCl 2 as catalyst in the presence of acetic acid and O 2 was also tested, as described by Maes and co‐workers;14 only traces of the desired product were detected (entry 16). However, when TBHP was used as oxidant in the presence of FeCl 2 , the product was obtained in good yield (78 %, entry 17).…”