title: rac-4-Carbamoylpiperidinium cis-2-car-boxy-cyclo-hexane-1-carboxyl-ate.
abstract: In the title racemic salt, C(6)H(13)N(2)O(+)·C(8)H(11)O(4) (-), formed from the reaction of cis-cyclo-hexane-1,2-dicarb-oxy-lic anhydride with isonipecotamide, the cations are linked into duplex chain substructures through both centrosymmetric cyclic head-to-head 'amide motif' hydrogen-bonding associations [graph set R(2) (2)(8)] and 'side-by-side' R(2) (2)(14) associations. The anions are incorporated into the chains through cyclic R(4) (3)(10) inter-actions involving amide and piperidinium N-H⋯O(carbox-yl) hydrogen bonds which, together with inter-anion carb-oxy-lic acid O-H⋯O(carbox-yl) hydrogen bonds, give a two-dimensional layered structure extending along (011).
authors.affiliation: Science and Engineering Faculty, Queensland University of Technology, GPO Box 2434, Brisbane, Queensland 4001,  Australia.
authors.forename: Graham
authors.initials: G
authors.lastname: Smith
authors.forename: Urs D
authors.initials: UD
authors.lastname: Wermuth