Crystal Structures of the Pentacoordinate Bromo, Isocyanato, Iodo, Acetato and Isothiocyanato Complexes of the meso-Tetraphenylporphyrinatomanganese Cation

Abstract

The room-temperature single-crystal X-ray diffraction determined structures of the Mn(tpp)Br.C₇H₈, Mn(tpp)(NCO), Mn(tpp)I.C₇H₈, Mn(tpp)(CO₂CH₃).0·5C₇H₈, and Mn(tpp)(NCS).0·5C₇H₈ complexs are described. The monoclinic P2₁/c unit cell of Mn(tpp)(NCO) has a 14·82(1), b 17·136(5), c 14·576(5) Å, β 111·41(5)°, V 3446(3) ų, Z 4. The refinement converged with conventional R(|F|) 0·053 for N_o 3199 (I > 3·0σ(I)) ‘observed’ reflections. The monoclinic P 2₁/m unit cell of Mn(tpp)Br.C₇H₈ has a 9·984(1), b 15·453(6), c 13·583(3) Å, β 103·99(2)°, V 2033(1) ų, Z 2, R 0·039 for N_o 2668. The Mn(tpp)I.C₇H₈ structure is triclinic, P^-1, with a 22·28(1), b 14·466(4), c 13·555(6) Å, α 76·32(3), β 81·74(4), γ 74·75(3)°, V 4079(3) ų, Z 4, R 0·050 for N_o 9039. The triclinic P^-1 crystal structures of the Mn(tpp)(CO₂CH₃).0·5C₇H₈ and Mn(tpp)(NCS).0·5C₇H₈ complexes are isomorphous. The Mn(tpp)(CO₂CH₃).0·5C₇H₈ structure has a 26·18(1), b 13·503(3), c 12·074(6) Å, α 66·08(4), β 81·36(4), γ 86·71(5)°, V 3858(3) ų, Z 4, R 0·075 for N_o 6388. Solvate disorder, requiring a rigid body model, islargely responsible for the relatively high residuals. The Mn(tpp)(NCS).0·5C₇H₈ structure has a 25·442(6), b 13·746(3), c 12·182(5) Å, α 66·97(3), β 78·59(3), γ 87·90(2)°, V 3839(2) ų, Z 4, R 0·061 for N_o 5506. The asymmetric units of the iodo, acetato and isothiocyanato structures each contain two crystallographically independent complex molecules that are sensitive to crystal packing forces. The metal ion displacements from the least-squares planes formed by the pyrrole nitrogen atoms are 0·299(1) and 0·274(1) Å for the Mn(tpp)(NCO) and Mn(tpp)Br.C₇H₈complexes, and 0·240(1) and 0·252(1), 0·281(1) and 0·278(1), and 0·243(1) and 0·244(1) Å for the independent (a) and (b) complex molecules of Mn(tpp)I.C₇H₈, Mn(tpp)(CO₂CH₃).0·5C₇H₈, and Mn(tpp)(NCS).0·5C₇H₈ respectively. The axial Mn–X bond lengths are 2·029(5) and 2·490(1) Å for the Mn(tpp)(NCO) and Mn(tpp)Br.C₇H₈ complexes, and 2·767(1) and 2·730(1), 2·028(5) and 2·010(5), and 2·067(6) and 2·072(5) Å for the (a) and (b) complex molecules of Mn(tpp)I.C₇H₈, Mn(tpp)(CO₂CH₃).0·5C₇H₈, and Mn(tpp)(NCS).0·5C₇H₈. One of the independent complex molecules in the Mn(tpp)(CO₂CH₃).0·5C₇H₈ structure appears to exhibit acetate coordination through a carbonyl oxygen.