Spectrum Chemical manufactures and distributes fine chemicals with quality you can count on including those with CAS number 84-58-2, Whether you call it 2,3-Dichloro-5,6-dicyano-1,4-benzoquinone, DDQ or 4 -5-Dichloro-3 -6-dioxo-1 -4-cyclohexadiene-1 -2-carbonitrile you can be assured the 2,3-Dichloro-5,6-dicyano-1,4-benzoquinone products offered by Spectrum, meet or exceed the grade requirements or specifications for each individual product.