1D Metal-Pyrimidine chain with antiferromagnetic coupling and spin-canting behavior

Two isostructural compounds [M(hpmc)(phen)(H2O)] [M = Mn (1), Co (2); H2hpmc = 6-hydroxypyrimidine-4-carboxylic acid, phen = 1,10-phenanthroline] were synthesized by the in-situ hydrothermal reactions of 6-chloropyrimidine-4-carboxylic acid (Clpmc) with MnII and CoII ions, in which the metal centers are bridged by pyrimidine ring to form 1D chain. Magnetic studies indicate pyrimidine can transmit antiferromagnetic coupling and the CoII complex shows spin-canting behavior below 3.5 K.

By in-situ hydrothermal reaction of 6-chloropyrimidine-4-carboxylic acid (Clpmc) with MnII and CoII ions, two isostructural pyrimidime-bridged 1D chain compounds [M(hpmc)(phen)(H2O)] [H2hpmc = 6-hydroxypyrimidine-4-carboxylic acid, phen = 1,10-phenanthroline] were firstly synthesized. Magnetic studies indicate pyrimidine can transmit antiferromagnetic coupling and the CoII complex shows spin-canting behavior below 3.5 K.Figure optionsDownload as PowerPoint slideHighlights
► Compounds 1 and 2 are the first examples of complexes bridged by 6-hydroxypyrimidine-4-carboxylic acid (H2hpmc).
► In-situ generation of 6-hydroxypyrimidine-4-carboxylic acid from 6-chloropyrimidine-4-carboxylic acid is firstly reported.
► The variable-temperature magnetic data indicate that pyrimidine ring in hpmc ligand transmits antiferromagnetic coupling in both 1 and 2.
► Compared with 1, 2 also shows spin-canting behavior due to the anisotropy of Co(II) ions.
► The fact that compounds of 1 and 2 with similar structure show different magnetic behavior varying with the magnetic anisotropy of spin carrier conduces to establish suitable model for understanding the influence of magnetic anisotropy on the final magnetic behavior of two isostructural compounds.