Syntheses and crystal structures of two trinuclear iron(III) carboxylate complexes: [Fe-3(mu(3)-O)(mu-O2CEt)(6)(H2O)(3)]Cl center dot 3H(2)O and [Fe-3(mu(3)-O)(mu-O2CEt)(6)PY3]Cl (Py = pyridine)

Two new oxo-centered trinuclear iron complexes [Fe-3 (mu(3)-O) (mu-O2CEt)(6 )(H2O)(3)]Cl . 3H(2)O 1 and [Fe-3(mu(3)-O) (mu-O2CEt)(6)PY3]Cl 2 were prepa red in non-aqueous solvent and their crystal structures have been determine d. Crystal 1 is monoclinic , space group P2(1)/n, a = 9. 909(3) , b = 24. 4 67(8), c = 14. 542(7) Angstrom , beta = 107. 85 (4)degrees V = 3356 (4) Ang strom (3) , Z = 4, M-r = 765. 52 , D-c = 1. 52 g/cm(3), mu = 14. 28 cm(-1), F(000) = 1588 and R = 0. 058, R-omega = 0. 071 for 3745 unique reflections with I> 3 sigma(I). Crystal 2 belongs to the monoclinic system with space group C2/c, a = 13. 750 (3), b = 18. 439(4), c = 16. 696(3) Angstrom , beta = 93. 42(3)degrees, V = 4826(3) Angstrom (3), Z = 4, Mr = 894. 73, D-c = 1 . 41 g/cm(3), mu = 11. 4 cm(-1)' F(000) = 2322 and R = 0. 058 , R-omega,= 0 . 062 for 2272 unique reflections with 1>3 sigma(I). The two structures con tain the same trimetal framework in which three iron(m) atoms form a nearly equilateral triangle with a mu(3)-oxygen atom in the centre.