A green and simple approach was developed for the regioselective synthesis of structurally diverse chromenopyrrole frameworks from 3-formylchromones, active methylenes, and α-azido ketones using piperidine as a catalyst in the aqueous medium through a tandem one-pot multicomponent reaction. Further, the synthesized pyrrole framework was successfully converted into biologically significant 6-azaindole derivatives in a simple synthetic transformation. An exciting feature of this synthetic protocol is that the reaction mechanism and formation of the products depend on the nature of the active methylene used. This approach has several advantages such as a transition-metal-free catalyst, a short reaction time, easy separation, an excellent yield, practically simple execution, high regioselectivity, very good atom economy, low E-factor, and no requirement of toxic solvents and chromatographic purification.

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In the title compound, C16H15BrN2O4, the six-membered carbocyclic ring of the chromene moiety adopts an envelope conformation with the disordered methyl­ene C atom as the flap. The pyran ring is almost orthogonal to the chloro­phenyl ring, making a dihedral angle of 87.11 (12)°. The amine-group N atom deviates significantly from the pyran ring [0.238 (3) Å]. The mol­ecular structure is stabilized by an intra­molecular N—H⋯O hydrogen bond, which generates an S(6) ring motif. In the crystal, mol­ecules are linked via C—H⋯O hydrogen bonds, which generate C(8) chains running parallel to the b axis. The chains are linked by C—H⋯π inter­actions. The methyl­ene-group C atom of the chromene system that is disordered, along with its attached H atoms and the H atoms on the two adjacent C atoms, has an occupancy ratio of 0.791 (7):0.209 (7).

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