2,3-Dichloro-5,6-dicyano-1,4-benzoquinone

2,3-Dichloro-5,6-dicyano-1,4-benzoquinone (or DDQ) is the chemical reagent with formula C₈Cl₂N₂O₂. This oxidant is useful for the dehydrogenation of alcohols, phenols and steroid ketones in organic chemistry. DDQ decomposes in water, but is stable in aqueous mineral acid

Mineral acid

A mineral acid is an acid derived from one or more inorganic compounds. A mineral acid is not organic and all mineral acids release hydrogen ions when dissolved in water.-Characteristics:...

.

Preparation

Synthesis of DDQ involves in cyanation

Cyanation

Cyanation is a term used in the chemical sciences to denote the attachment or substitution of a cyanide group on various substrates....

 and chlorination

Chlorination

Chlorination is the process of adding the element chlorine to water as a method of water purification to make it fit for human consumption as drinking water...

 of benzoquinone. Thiele

Johannes Thiele (chemist)

Friedrich Karl Johannes Thiele was a German chemist and a prominent professor at several universities, including those in Munich and Strasbourg. He developed many laboratory techniques related to isolation of organic compounds...

 and Günther first reported a 6-step preparation in 1906. A single-step chlorination from 2,3-dicyanohydroquinone was reported by Walker and Waugh in 1965.

Stability

DDQ can react with water and give off hydrogen cyanide (HCN), which is highly toxic. Storage should be in dry area. Low temperature and weak acid environment can increase the stability of DDQ.

3.Oxidative Coupling

External links

• "Like Neurons in the Brain": A Molecular Computer that Evolves