rac-1-(4-tert-Butyl-phen-yl)-5-ethyl-4-ferrocenyl-5-hy-droxy-1H-pyrrol-2(5H)-one

The title compound, [Fe(C₅H₅)(C₂₁H₂₄NO₂)], which is produced by the oxidation of 1-(4-tert-butyl-phen-yl)-2-ethyl-3-ferrocenyl-pyrrole, crystallizes as a racemic mixture in the centrosymmetric space group P2₁/n. The central heterocyclic pyrrole ring system subtends dihedral angles of 13.7 (2)° with respect to the attached cyclo-penta-dienyl ring and of 43.6 (7)° with the major component of the disordered phenyl group bound to the N atom. The 4-tert-butyl-phenyl group, as well as the non-substituted Cp ring are disordered with s.o.f. values of 0.589 (16) and 0.411 (16), respectively. In the crystal, mol-ecules with the same absolute configuration are linked into infinite chains along the b-axis direction by O-H⋯O hydrogen bonds between the hy-droxy substituent and the carbonyl O atom of the adjacent mol-ecule.