Preferred Label : photocycloaddition; 
IUPAC definition : intermolecular photochemical process leading to carbo- or hetero- cyclic ring systems
               by formation of two new single bonds, either by a concerted process (e.g., a concerted
               addition) or by multi-step processes (e.g., the Paternò–Büchi reaction).; 
Scope note : triplet state photocycloadditions are two-step processes involving the formation of
               diradical intermediates.; 
         
         
            Origin ID : PT07451; 
 See also See also
 
         
         
         intermolecular photochemical process leading to carbo- or hetero- cyclic ring systems
            by formation of two new single bonds, either by a concerted process (e.g., a concerted
            addition) or by multi-step processes (e.g., the Paternò–Büchi reaction).