2-(4-Methyl­phen­yl)-7-(2-methyl­prop­oxy)-4H-chromen-4-one–6-chloro-2-(4-methyl­phen­yl)-7-(2-methyl­prop­oxy)-4H-chromen-4-one (19/1)

The title co-crystal, 0.95C(20)H(20)O(3)·0.05C(20)H(19)ClO(3), arises as the chloride carried over during the synthesis shares a position with an aromatic H atom; the partial occupancies are 0.947 (2) and 0.053 (2) for H and Cl, respectively. The mol­ecular structure is stabilized by intra­molecular C—H⋯O contacts, forming pseudo five- and six-membered rings with S(5) and S(6) graph-set motifs, respectively. The crystal structure features π–π stacking inter­actions between the centroids of the central fused ring systems [centroid–centroid distance = 3.501 (2) Å].