Application of 2,3-Dichloro-5,6-dicyano-1,4-benzoquinone (DDQ)

DESCRIPTION

2,3-Dichloro-5,6-dicyano-1,4-benzoquinone (or DDQ) is the chemical reagent with formula C6Cl2(CN)2O2. This oxidant is useful for the dehydrogenation of alcohols, phenols, and steroid ketones in organic chemistry.

APPLICATION

DDQ is a deprotection agent for ketals, acetals, and thioacetals. It is a useful electron transfer reagent for synthesis of quinolones and an oxidizing agent used to synthesize steroids. 

2,3-Dichloro-5,6-dicyano-p-benzoquinone (DDQ) can be used as: A deprotecting reagent for a variety of compounds, such as thioacetals, acetals and ketals.  An electron-transfer reagent for the synthesis of quinolines from imines and alkynes or alkenes.  An effective reagent for the benzylic and allylic C-H functionalization. An oxidizing agent for the synthesis of functionalized furans and benzofurans.

To a solution of 9,10-diphenylanthracene (200 mg, 0.61 mmol) and DDQ (412 mg, 1.8 mmol, 3.0 equiv) in dichloromethane (19 mL) was added TfOH (1 mL) at 0 °C and the mixture was stirred for 1 hour. The reaction mixture was quenched with sat. NaHCO3 aq. (20 mL), filtered through celite pad and the insoluble was washed with dichloromethane (100 mL). The organic layer was washed with sat. NaHCO3 aq. and dried over Na2SO4.The solvent was removed under reduced pressure and the residue was purified by column chromatography (hexane:dichloromethane = 0:1 - 1:3 on silica gel) to give rubicene (131 mg, 67%) as a red solid.