1,4-Amino-N,N-dimethylaniline,dihydrochloride

white to beige to grey powder

It is a stain used in microscopy. N,N-Dimethyl-p-phenylenediamine dihydrochloride is also suitable for use in the peroxidase test. It is a compound that is normally used to measure the antioxidant potential.

N,N-Dimethyl-p-phenylenediamine dihydrochloride (DMPD) is used for the determination of peroxidase. DMPD is converted into a red pigment of semiquinone nature. It is also used in the HID-AB (high iron diamine-alcian blue) staining procedures, which are used to differentiate between sialomucin and sulfomucin in the gastrointestinal tract.

A method for the preparation of 1,4-Amino-N,N-dimethylaniline,dihydrochloride, comprising the steps of:
(1) Take 1 mole of p-nitrochlorobenzene and dissolve it in 400 ml of toluene to obtain solution A;
(2) Take 1.1 mole of dimethylamine hydrochloride dissolved in 180 ml of water, add solution A;
(3) 2025, under stirring, add 1.1 mole of 15% sodium hydroxide aqueous solution to the above solution dropwise, warm up to 35, add 0.66 mole of 15% sodium hydroxide aqueous solution dropwise again in 30 minutes, and then keep warm and react for 60 minutes;
(4) Stilling, phase separation, toluene layer with active nickel catalyst, hydrogen reduction;
(5) Separation of the catalyst by filtration; the toluene layer is passed through hydrogen chloride gas to give a precipitate of N,N-dimethyl-p-phenylenediamine dihydrochloride;
(6) Centrifugation, obtained 1,4-Amino-N,N-dimethylaniline,dihydrochloride 198g, content 99.7%, yield 94.5% (as p-chloronitrobenzene).