- The fission of a bond originating at an atom which is adjacent to one assumed to bear the charge; the definition of β-, γ-, cleavage then follows automatically. The process: A00004.pngwould thus be described as α-fission of a ketone with expulsion of a radical R1·. The carbon atoms of the radical R1· are called the α-, β-, γ-carbons, starting with the atom nearest the @F02555@.
- Homolytic cleavage of a bond connecting an atom or group to an excited @C01076@. Often applied to a bond connected to a carbonyl group, in which case it is called a @N04219@Note:
This reaction should be distinguished from an @A00007@