Crystal structures of 1-(4-chloro­phen­yl)-4-(4-methyl­phen­yl)-2,5-dioxo-1,2,5,6,7,8-hexa­hydro­quinoline-3-carb­oxy­lic acid and 4-(4-meth­oxy­phen­yl)-1-(4-methyl­phen­yl)-2,5-dioxo-1,2,5,6,7,8-hexa­hydro­quinoline-3-carbo­nitrile

In the title compounds C(23)H(21)ClN(2)O(3) [I, namely 1-(4-chloro­phen­yl)-4-(4-methyl­phen­yl)-3,8-dioxo-1,2,5,6,7,8-hexa­hydro­quine-3-carb­oxy­lic acid] and C(24)H(22)N(2)O(3) [II, namely 4-(4-meth­oxy­phen­yl)-1-(4-methyl­phen­yl)-2,5-dioxo-1,2,5,6,7,8-hexa­hydro­quinoline-3-carbo­nitrile], each of the cyclo­hexene and di­hydro­pyridine rings of the 1,2,5,6,7,8-hexa­hydro­quinoline moieties adopts a twisted-boat conformation. The asymmetric units of both compounds I and II consist of two independent mol­ecules (A and B). In II A, three carbon atoms of the cyclo­hexene ring are disordered over two sets of sites in a 0.670 (11):0.330 (11) occupancy ratio. In the crystal of I, mol­ecules are linked through classical N—H⋯O hydrogen bonds, forming inversion dimers with an R (2) (2)(8) ring motif and with their mol­ecular planes parallel to the crystallographic (020) plane. Non-classical C—H⋯O hydrogen-bonding inter­actions connect the dimers, resulting in a three-dimensional network. In the crystal of II, mol­ecules are linked by C—H⋯N, C—H⋯O and C—H⋯π inter­actions, forming a three-dimensional network.