Description
2-bromo-5-fluoroaniline: a intermediate of antitumor drug.
2-bromo-5-fluoroaniline is the intermediate of antitumor drug Phortress, phortress is the benzothiazoles CYP1A1 antitumor drugs targeting by Univ Nottingham UK invention, solution becomes lipophilic compound 5F2O3(10 in the sensitive cells but Phortress enters), the latter is as potential aromatic hydrocarbon receptor (AhR) agonist, induce CYP1A1 to express, CYP1A1 metabolism through expressing produces and has high electrophilic active substance again, finally causes DNA damage and apoptosis. The method that, at present, synthetic 2-bromo-5-fluoronitrobenzene prepares 2-bromo-5-fluoroaniline is divided into two large classes:
The one: adopt a chemical reduction method, utilizing the chemical reducing agent reductase 2-bromo-5-fluoronitrobenzenes such as protochloride glass putty, iron powder, vat powder, hydrazine, and sodium borohydride (potassium), which is 2-bromo-5-fluoroaniline.
The 2nd: adopt hydro-reduction. What we do more often both at home and abroad at present is chloride or the catalytic hydrogenation of fluorine-containing arylamine, and the brominated less report of arylamine hydrogenation mainly is easily by hydrogenolysis because of bromine.
Synthesis
A preparation method of 2-Bromo-5-fluoroaniline is as follows: methanol, 2-bromo-5-fluoronitrobenzene, W-4 type Raney nickel and bromine inhibitor are put into a hydrogenation kettle to carry out hydrogenation reaction. After the reaction is completed, the reaction solution is filtered under nitrogen protection. The filtered filtrate is then distilled under reduced pressure to remove methanol, and n-hexane is added. Then, the product is washed with process water, and after washing, the product is allowed to stand and separate. Then, the organic phase is cooled and crystallized, an off-white to brownish-yellow solid is precipitated, and a wet product is obtained by suction filtration. The wet product is dried to obtain the finished product 2-Bromo-5-fluoroaniline.