An efficient, one-pot quantitative procedure for the preparation of benzo[a]pyrano[2,3-c]phenazine derivatives from four-component condensation reaction of 2-hydroxynaphthalene-1,4-dione, benzene-1,2-diamine, aromatic aldehydes, and malononitrile in the presence of [(EtO)3Si(CH2)3N+H3][CH3COO−] as basic ionic liquid as catalyst under solvent-free conditions is described. Simple procedure, high yields, short reaction times, and an environmentally benign method are advantages of this protocol. The [(EtO)3Si(CH2)3N+H3][CH3COO−] can be recovered and reused several times without loss of its activity.