Diethylsuccinoylsuccinate is an organic compound with the formula [CH<sub>2</sub>C(OH)=C(CO<sub>2</sub>Et)]2 (Et = ethyl). A tetrasubstituted derivative of 1,4-cyclohexadiene, the compound is the enol tautomer of the corresponding cyclohexadione.[1] It is produced by base-induced condensation of diethyl succinate:
2 EtO2CCH2CH2CO2Et [CH<sub>2</sub>C(OH)=C(CO<sub>2</sub>Et)]2 + 2 EtOH
Diethylsuccinylsuccinate is valued as a precursor to the quinacridone pigments. For example, it reacts with two equiv of anilines to give the diamines [CH<sub>2</sub>C(N(H)Ar)=C(CO<sub>2</sub>Et)]2, which undergoes cyclization upon treatment with acid to give dihydroquinacridone.[2] [3]
When heated in the presence of acid, diethylsuccinoylsuccinate converts to 1,4-cyclohexanedione via hydrolysis of the esters followed by decarboxylation.[4]