Effective preparation of cycloheptimidazol-4-one compounds

Motoharu Sonegawa1, Yoshinori Iwai, Hiroshi Tomiyama

  • 1Kotobuki Research Laboratories, Kotobuki Seiyaku Company Ltd., 6351 Sakaki-Machi, Nagano 389-0697, Japan. ktb-g121@kotobuki-pharm.co.jp

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Preparation of Amides

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In the presence of an aqueous base and a halogen, primary amides can lose the carbonyl (as carbon dioxide) and undergo rearrangement to form primary amines. This reaction, called the Hofmann rearrangement, can produce primary amines (aryl and alkyl) in high yields without contamination by secondary and tertiary amines.
Preparation of Acid Anhydrides01:07

Preparation of Acid Anhydrides

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Preparation of 1° Amines: Azide Synthesis01:22

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Introduction
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