Sodium Dithionite → N4-(3-Ethynylphenyl)quinazoline-4,6-diamine

Participants

Reaction Steps

(3-Ethynyl-phenyl)-(6-nitro-quinazolin-4-yl)-amine hydrochloride (500 mg, 1.50 mmol) was dissolved in 10 mL of formic acid and treated portion-wise with sodium dithionite (1.10 g, 6.28 mmol) at room temperature. After 2 hours the mixture was quenched with 120 mL of water and filtered. The filtrate was evaporated in vacuo to a residue which was dissolved in 100 mL of 1:1 methanol:chloroform, filtered and evaporated in vacuo to a second residue. This was triturated with 200 mL of 5% sodium bicarbonate for 30 minutes, filtered, washed with water and dried in vacuo for 16 hours. Flash chromatography on silica gel eluted with ethyl acetate afforded pure (6-aminoquinazolin-4-yl)-(3-ethynylphenyl)-amine; 140 mg (34%); mp 165° C. dec.

Provenance & Evidence