Chloranil → 6-Nitro-2-(1,3-benzodioxole-5-yl)-quinazoline

Beteiligte Stoffe

Reaktionsschritte

To a suspension of 5-nitro-2-amino-benzylamine hydrochloride (31 g, 0.152 mol) in DCM (450 ml) was added at 0° C. TEA (52.6 ml, 0.38 mol) and a solution of piperonyloyl chloride (27.3 g, 0.16 mol) in DCM (80 ml). The mixture was stirred for 2 hours at r.t. The solvent was removed i.v. and the residue triturated with ethanol/water 1/9, then with diisopropyl ether. The obtained solid was dried and suspended in toluene (900 ml) and POCl3 (670 ml). The mixture was heated at reflux for 2 hours, then the solvent was removed i.v. and the residue was triturated with water/ammonia, washed with water, dried over P2O5. A mixture of the obtained product and chloranil (32.7 g, 0.129 mol) in toluene (500 ml) was heated at reflux for 2 hours. The mixture was concentrated i.v. and the residue was triturated with NaOH 1M, washed with water and with methanol. The obtained solid was dried i.v. (37 g, 82.5% yield). C15H9N3O4, MW: 295.26, mp 220-222° C.

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