Novel Intercalation Host System Based on Transition Metal (Fe2+, Co2+, Mn2+)−Chloranilate Coordination Polymers. Single Crystal Structures and Properties

The new iron(II), cobalt(II), and manganese(II) intercalation compounds {[M(CA)(H 2 O) 2 ](G)} n (M = Fe 2+, Co 2+, Mn 2+; H 2 CA = chloranilic acid (C 6 H 2 O 4 Cl 2 ); G = H 2 O and phenazine (C 12 H 8 N 2; phz)) have been synthesized and characterized. {[Fe(CA)(H 2 O) 2 ](H 2 O)} n ( 1a ) crystallizes in the monoclinic space group C 2/ c (No. 15) with a = 4.914(2) Å, b = 14.222(2) Å, c = 13.987(2) Å, β = 94.98(2)°, V = 973.8(4) Å 3, and Z = 4. {[Fe(CA)(H 2 O) 2 ](phz)} n ( 2a ) crystallizes in the triclinic space group P 1̄ (No. 2) with a = 8.079(2) Å, b = 11.366(3) Å, c = 5.055(2) Å, α = 96.57(3)°, β = 98.70(3)°, γ = 83.07(2)°, V = 453.3(3) Å 3, and Z = 1. {[M(CA)(H 2 O) 2 ](H 2 O)} n (M = Co 2+ ( 1b ), Mn 2+ ( 1c )) are isomorphous to 1a . For 1 a − c, crystal structures consist of uncoordinated guest water molecules and one-dimensional zigzag [M(CA)(H 2 O) 2 ] k chains. Two water molecules occupying cis positions and two chloranilate filling the remaining sites in a bis bidentate fashion create the octahedral environment around the metal ion to form a zigzag chain (type I), which extends along the diagonal between the a and c axes. The adjacent chains are interlinked by hydrogen bonds, thus forming layers, which spread out along the ac plane. Water molecules are intercalated between the {[M(CA)(H 2 O) 2 ] k } l layers. The intercalation mode of the water molecules is different from those in {[M(CA)(H 2 O) 2 ](phz)} n (M = Fe 2+ ( 2a ), Co 2+ ( 2b ), Mn 2+ ( 2c )), which are isomorphous each other. The crystal structures of 2 a − c consist of uncoordinated phenazine molecules and straight [M(CA)(H 2 O) 2 ] k chains (type II). Infinite, nearly coplanar linear chains are formed by metal ions and the bis-chelating CA 2 - anions, which extend along the a direction, and are linked by hydrogen bonds between the coordinated water and the oxygen atoms of the CA 2 - on the adjacent chains, forming a two-dimensional sheet, which spreads out along the ac plane. The intercalated phenazines are stacked along the c axis perpendicular to the [M(CA)(H 2 O) 2 ] k chain, and the planes of the phenazine molecules are tilted to the stacking direction, forming a segregated columnar structure between the {[M(CA)(H 2 O) 2 ] k } l layers. The 57 Fe Mössbauer spectra of 1a and 2a consist of a single quadrupole doublet with IS = 1.16 mm/s ( 1a ), 1.16 mm/s ( 2a ) and QS = 2.53 mm/s ( 1a ), 1.46 mm/s ( 2a ) at 298 K, indicating that the oxidation state of the iron in both complexes is two. The magnetic susceptibilities were measured from 2 to 300 K and analyzed by a one-dimensional Heisenberg-exchange model to yield J = −0.74 cm - 1, g = 2.01, ρ = 1.4% ( 1c ) and J = −0.65 cm - 1, g = 2.02, ρ = 9.0% ( 2c ).