Ethyl and isopropyl 4-ferrocenyl-benzoate.

The title compounds, [Fe(C(5)H(5))(C(14)H(13)O(2))] and [Fe(C(5)H(5))(C(15)H(15)O(2))], respectively, contain the ferrocenyl eta(5)(C(5)H(4)) and phenylene -C(6)H(4)- rings in a nearly coplanar arrangement, with interplanar angles of 6.88 (12) and 10.5 (2) degrees, respectively. Molecules of the ethyl ester form dimers through eta(5)(C(5)H(5))C-H...O=C hydrogen bonds, with graph set R(2)(2)(20), and, together with Csp(3)-H.pi(C(5)H(5)) interactions, generate a one-dimensional column (irregular ladder). Molecules of the isopropyl ester aggregate through eta(5)(C(5)H(5))C-H.pi(C(6)H(4)) interactions.