Dibenzylammonium hydrogen maleate and a redetermination at 120 K of bis(dibenzylamino)methane

In dibenzylammonium hydrogen maleate or dibenzylammonium (2Z)‐3‐carboxyprop‐2‐enoate], C₁₄H₁₆N⁺·C₄H₃O₄^?, (I), the anion contains a fairly short and nearly linear O—H...O hydrogen bond, with an O...·O distance of 2.4603 (16) Å, but with the H atom clearly offset from the mid‐point of the O...O vector. The counter‐ions in (I) are linked by two N—H...O hydrogen bonds to form C₂²(6) chains and these chains are weakly linked into sheets by a C—H...O hydrogen bond. Bis(dibenzylamino)methane, C₂₉H₃₀N₂, (II), crystallizes with two independent molecules lying across twofold rotation axes in the space group C2/c, and the molecules are conformationally chiral; there are no direction‐specific intermolecular interactions in the crystal structure of (II).