The 1:1 adduct of Kemp's triacid with 2‐aminopyridine

The crystal structure determination of the molecular proton‐transfer adduct of Kemp's triacid (cis‐cis‐1,3,5‐tri­methyl­cyclo­hexane‐1,3,5‐tri­carboxylic acid, KTA) with 2‐amino­pyridine (2‐APY), namely 2‐amino­pyridinium 3,5‐di­carboxy‐1,3,5‐tri­methyl­cyclo­hexane­carboxyl­ate, 2‐APY⁺·KTA^? or C₅H₇N₂⁺·C₁₂H₁₇O₆^?, has revealed a centrosymmetric hydrogen‐bonded cyclic KTA homodimer repeating unit [O?O 2.524 (4) Å] linked into a polymer structure through the pyridinium and amino groups of the 2‐APY mol­ecule [O?N 2.736 (4), 2.989 (4) and 2.999 (4) Å].