Rich Magnetic Chemistry of Cobalt(II) Complexes with N ‐Phosphorylthioureas. Crystal Structure and Solution 1 H NMR Spectral Properties

Structure and magnetic properties of Co II complexes with N ‐phosphorylthiourea derivatives {RC(S)NHP(O)(O i Pr) 2 } ( HL ) [Co{Et 2 NC(S)NP(O)(O i Pr) 2 } 2 ] ( 1 ), [Co{ i PrNHC(S)NP(O)(O i Pr) 2 } 2 ] ( 2 ), [Co{[ t BuNHC(S)NP(O)(O i Pr) 2 } 2 ] ( 3 ), [Co{p‐MeOC 6 H 4 NHC(S)NP(O)(O i Pr) 2 } 2 ] ( 4 ), [Co{p‐BrC 6 H 4 NHC(S)NP(O)(O i Pr) 2 } 2 ] ( 5 ) were investigated. Paramagnetic shifts in the 1 H NMR spectrum were observed for high‐spin Co II complexes with HL , incorporating amidophosphate moiety C(S)NP(O). The thermal dependence of the magnetic susceptibility has shown that the extended materials 2 , 3 and 5 show ferromagnetic exchange between distorted tetrahedral metal atoms, while in complex 4 antiferromagnetic behavior takes place. Compound 1 behaves as a spin‐canted ferromagnet, an antiferromagnetic ordering taking place below a critical temperature, T c = 175 K. Complex 2 was investigated by single crystal X‐ray diffraction. The cobalt(II) atom in complex 2 is in distorted tetrahedral CoO 2 S 2 environment formed by the C=S sulfur atoms and the P=O oxygen atoms of two deprotonated ligands.