Hydrogen abstraction

Hydrogen atom abstraction or hydrogen atom transfer (HAT) in chemistry is any chemical reaction in which a hydrogen free radical is abstracted from a substrate according to the general equation:

X^. + H-Y -> X-H + Y^.

Examples of HAT reactions are oxidative reactions in general, hydrocarbon combustion and reactions involving containing an iron(V)-oxo unit. The abstractor is usually a radical species itself. An example of a closed-shell abstractor is chromyl chloride. HAT can take place through proton-coupled electron transfer.

It is reported in literature that during the synthesis of a Coelenterazine derivative, a non-radical hydrogen abstraction was observed on a substituted aminoimidazole in a typical Sandmayer hyroxilation condition.

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