3-Methyl-2-vinylpyridinium phosphate

In the title salt, C8H10N+·H2PO4 , the cation is essentially planar (r.m.s. deviation = 0.063 ). In the crystal, the phosphate anions form inversion R22(8) dimers via pairs of O—H...O hydrogen bonds. These dimers are further linked by pairs of O—H...O hydrogen bonds, also enclosing R22(8) loops, forming chains running along [001]. The cations are bonded to the anions via N—H...O hydrogen bonds and C—H...O contacts.