Complex sentence: The Wolff rearrangement is a rearrangement reaction converting a α-diazo-ketone into a ketene in a photochemical reaction, by application of heat, by microwave chemistry or with a transition metal catalyst such as silver oxide.
Split into simpler sentences: The Wolff rearrangement is a rearrangement reaction converting a α-diazo-ketone into a ketene. The rearrangement is catalyzed by light, heat, or a transition metal catalyst such as silver oxide.