It is an important raw material and intermediate used in organic synthesis, pharmaceuticals, agrochemicals and dyestuff.
The synthesis of 6-BROMO-2,4-DICHLOROQUINAZOLINE is as follows:BTC (0.65 g, 2.2 mmol in 6mL of PhCl) was added to astirred solution of tris(4-methoxyphenyl)phosphine oxide 3d(0.33 g, 0.9 mmol in 5mL PhCl) dropwise in a round botttomflask placed on an ice bath. After complete addition,the mixture was stirred for 30 min at room temperature.Then isatin-3-oximes (3 mmol) were added, and the mixturewas heated to 120 C until completion of the reaction(followed by TLC, n-hexane/ethyl acetate 10:1). Aftercooling, the mixture was then poured into 50mL ice waterand extracted with ethyl acetate (320 mL). The organiclayer was dried over anhydrous Na
2SO
4 and concentrated invacuo. The crude product was purified over column chromatography(n-hexane/ethyl acetate 10:1) to afford thepure produce 2,4-dichloroquinazolins. Tris(4-methoxyphenyl)phosphine oxide 3d was recovered by column chromatography(n-hexane/ethyl acetate 1:1).
[1] Pharmaceutical Chemistry Journal, 1987, vol. 21, # 7, p. 478 - 483
[2] Khimiko-Farmatsevticheskii Zhurnal, 1987, vol. 21, # 7, p. 802 - 807
[3] Bioorganic and Medicinal Chemistry Letters, 2017, vol. 27, # 21, p. 4904 - 4907
[4] Bioorganic and Medicinal Chemistry, 2017, vol. 25, # 24, p. 6680 - 6694
[5] Patent: WO2012/87938, 2012, A1. Location in patent: Page/Page column 114
