Amidine

Amidines are a class of oxoacid derivatives.

The oxoacid from which an amidine is derived must be of the form R_nE(=O)OH, where R is a substituent. The −OH group is replaced by an −NH₂ group and the =O group is replaced by =NR, giving amidines the general structure R_nE(=NR)NR₂ ^{[1] [2] [3]}.

The skeletal formula of acetamidine

When the parent oxoacid is a carboxylic acid, the resulting amidine is a carboxamidine, and has the following general structure:

Carboxamidines are frequently referred to simply as amidines, as they are the most commonly-encountered type of amidine in organic chemistry. The simplest amidine is formamidine, HC(=NH)NH₂.

Examples of amidines include DBU and diminazene.

The most common way to make primary amidines is by the Pinner reaction

Amidinate salts

An amidinate salt has the general structure M⁺[RNRCNR]^{- [4]} and can be accessed by reaction of a carbodiimide with an organometallic compound such as methyl lithium.

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