The review summarizes published data on the most important intramolecular a
ldol condensations and crotonizations of aliphatic, arylaliphatic, hetaryla
liphatic, and semicyclic 1,5-diketones and their oxo derivatives and 2,2'-a
lkylidene- and 2,2'-arylmethylenedicycloalkanones. Carbocyclization process
es involving 1,5-diketones as intermediates are considered, and possible ut
ilization of the products is discussed.