3-Benzylidene-2,4-pentanedione may be used in the preparation of:Five membered cyclic oxyphosphoranes by reacting with phosphonite esters.5-Hydroxy-N-substituted-2H-pyrrol-2-ones by reacting with alkyl isocyanides.3-Benzylidene-2,4-bis (trimethylsilyloxy)-1,4-pentadiene via trimethylsilylation.