We report a three-dimensional Fe(ii) porous coordination polymer that exhibits a spin crossover temperature change following CO2 sorption (though not N2 sorption). Furthermore, single crystals of the desolvated polymer with CO2 molecules at three different temperatures were characterised by X-ray crystallography.

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A series of late transition metal complexes, [(bpma)Co(μ–Cl)Cl]2, [(bpma)Cu(μ–Cl)Cl]2, [(bpma)Zn(μ–Cl)Cl]2 and [(bpma)Cd(μ–Br)Br]2 (where bpma is 4‐bromo‐N‐((pyridin‐2‐yl)methylene)benzenamine) have been synthesized and structurally characterized. The X‐ray structures of dimeric complexes [(bpma)M(μ–X)X]2 (M = Co, Cu and Zn, X = Cl; M = Cd, X = Br) showed a distorted 5‐coordinate trigonal bipyramidal geometry involving two nitrogen atoms of N,N‐bidentate ligand, two bridged and one terminal halogen atoms. The complex [(bpma)Cu(μ–Cl)Cl]2 revealed the highest catalytic activity for the polymerisation of methyl methacrylate in the presence of modified methylaluminoxane with an activity of 9.14 × 104 g PMMA/mol·Cu·h at 60 °C and afforded syndiotactic poly (methylmethacrylate) (rr = 0.69).

4CH 3 OH (2) coordination complexes have been prepared by the reaction of the tetradentate H 2 pmide ligand and Cu(NO 3 ) 2 ·3H 2 O or Co(CH 3 CO 2 ) 2 ·4H 2 O/NaNCS in organic solvent (H 2 pmide = N-(2-pyridylmethyl)iminodiethanol). In 1, one copper(II) ion is bonded with a H 2 pmide, and the other is coordinated with a mono-deprotonated Hpmide − . The copper(II) ions are linked through an ethoxo group of the Hpmide − ligand and two oxygen atoms of a nitrate ion, resulting in an asymmetric dinuclear structure. In 2, two terminal cobalt(III) units are coordinated with pmide 2− , NCS − , and CH 3 CO 2 − . The terminal units are each connected to a central cobalt(II) cation through the two oxygen atoms of pmide 2− and one bridged acetate ion, giving rise to a mixed-valence trinuclear cobalt complex formulated as Co III -Co II -Co III . Complex 1 shows a strong antiferromagnetic interaction through the ethoxo and nitrato groups between the copper(II) ions [g = 2.070, J = -88.1 cm −1 (-61.2 K)]. However, complex 2 behaves as a paramagnetic cobalt(II) monomer, due to the diamagnetic cobalt(III) ions in the terminal units [g = 2.526, |D| = 51.8 cm −1 (36.0 K)]. † CCDC 1402754 and 1402755. For crystallographic data in CIF or other electronic format see

Dinuclear Fe and Ni complexes, [(phenO)Fe(N )] (NO ) (1) and [(phenOH)Ni(N ) ] (2), were prepared by treating Fe(NO ) ⋅9 H O and Ni(NO ) ⋅6 H O in methanol, respectively, with phenOH (=N-(2-pyridylmethyl)-N'-(2-hydroxyethyl)ethylenediamine) and NaN ; both 1 and 2 were characterized by elemental analysis, IR spectroscopy, X-ray diffraction, and magnetic susceptibility measurements. Two ethoxo-bridged Fe and two azido-bridged Ni were observed in 1 and 2, respectively; corresponding antiferromagnetic interaction via the bridged ethoxo groups and strong ferromagnetic coupling via the bridged end-on azido ligands within the dimeric unit were observed. Complex 1 did not exhibit any catalytic activity, while 2 exhibited excellent catalytic activities for the epoxidation of aliphatic, aromatic, and terminal olefins.