Synthesis and Reactivity of Discrete Calcium Imides

Benjamin M Wolf1, Cäcilia Maichle-Mössmer1, Reiner Anwander2

  • 1Institut für Anorganische Chemie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, 72076, Tübingen, Germany.

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Amides are synthesized by treating carboxylic acids with amines in the presence of dehydrating agents like dicyclohexylcarbodiimide (DCC).
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Subsequently, the amine acts as a nucleophile that attacks the acylating agent to form a tetrahedral intermediate. In the...
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Imine formation involves the addition of carbonyl compounds to a primary amine. It begins with the generation of carbinolamine through a series of steps involving an initial nucleophilic attack and then several proton transfer reactions. The second part includes the elimination of water, as a leaving group, to give the imine.
Imines are formed under mildly acidic conditions. A pH of 4.5 is ideal for the reaction.
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Primary amines react with carbonyl compounds—aldehydes and ketones—to generate imines. Imines consist of a C=N double bond and are named Schiff bases after its discoverer—the German chemist Hugo Schiff. On the other hand, secondary amines react with carbonyl compounds to give enamines. In enamines, the presence of a C=C double bond adjacent to the nitrogen atom leads to the delocalization of the lone pair.
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