Reaction with Ammonia, Amines, and their Derivatives

Reaction with Ammonia, Amines, and their Derivatives 

The ring-opening of oxiranes with ammonia and amines is one of the general methods for the preparation of 1,2-aminoalcohols. This procedure has acquired great importance in practice too. The process is illustrated in a new example in Eq. 317.  

When oxiranes are reacted with enamines, 7-hydroxyketones are formed (Eq. 318).i2  

The effect of a heteroatom 0 to the oxirane ring has been studied in the reaction of monosubstituted oxiranes 131 and benzylamine. If X = 0, the reaction occurs via the transition state 132 with neighbouring-group participation. Neighboring-group participation has similarly been observed in the reactions of mono- and tri-substituted oxiranes and )3-substituted primary amines. The product ratio of the aminoalcohols formed from the reactions of a-vinyloxiranes and primary amines depends on the geometry of the oxirane.Base-catalyzed addition of oxiranes to oximes leads not only to 0-alkyl but to A -alkyl derivatives (Eq, 319).  

Oxiranes react with 1,2,4-triazoles in the presence of acetic acid or formic acid (Eq. 320).  

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