Die Oxydation von Alkylpyridinen mit Selendioxyd

Abstract

Die Oxydation von Alkylpyridinen durch Selendioxyd ohne Zusatz fremder Lösungs- bzw. Verdünnungsmittel gestattet die Gewinnung von Pyridincarbonsäuren. Das Verfahren eignet sich auch zur Darstellung von Pyridincarbonsäuren, die leicht Kohlendioxyd abspalten. Die selektive Eigenschaft des Selendioxyds, mit Alkylgruppen in 3-Stellung des Pyridinkernes nicht zu reagieren, bleibt dabei voll erhalten. Pyridin und Methylpyridin sowie Chinolin und Isochinolin bilden unter Wasserauschluß mit Selendioxyd kristallisierte Addukte, deren Darstellung und Eigenschaften beschrieben werden

Novel peptidomimetic peptide deformylase (PDF) inhibitors of Mycobacterium tuberculosis

“…The pure glyoxylic acids 2a – j (76%–54%) were obtained by column chromatography using ethyl acetate: n‐hexane (90:10) and characterized by melting points and FTIR similar to reported compounds. (Hatanaka & Ishimaru, 1973; Jerchel, Bauer, & Hippchen, 1955; Wadhwa et al., 2008).…”

Kinetics of the Highly Selective Liquid-Phase Oxidation of Side Chain Alkyl Groups in 2-Methylpyrazine and Picolines by Selenium Dioxide

“…They are commonly synthesized by the oxidation of 2-methylpyrazine, 3-picoline, 4-picoline, and 2-picoline, respectively. Different oxidizing agents such as air, − nitric acid, , and selenium dioxide − can be used for this type of oxidation. In air-oxidation the use of costly catalysts and highly corrosive promoters such as bromide salts in acetic acid solvent at elevated temperature makes the process somewhat complicated from both cost and design points of view.…”

Synthetic Studies on Pseudo‐Dimeric Lycopodium Alkaloids: Total Synthesis of Complanadine B

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