• The formation of the diester is not part of the Dieckmann reaction, and occurs by 2 conjugate addition steps.
• This reaction is the intramolecular version of the Claisen reaction.
• The ring closure step is classified as 5-exo-trig according to the Baldwin rules.
• The reaction is often used to form heterocycles - the product can easily be hydrolysed and decarboxylated to form a heterocyclic ketone.


References:

• Lin R.; Castells J.; Rapoport H.; J. Org. Chem., 1998, Volume 63, Issue 12, 4069-4078
• Miyaoka H.; Honda D.; Mitome H.; et al. Tetrahedron Lett., 2002, Volume 43, Issue 43, 7773-7775