Book Description
"As part of a project directed towards elucidating the characteristics of ligands which coordinate to give complexes having tetrahedral structures, a study of chelates containing the bulky quinuclidine group has been made. With 2-(N-morpholinylmethyl)-3-quinuclidinone (MQN), complexes having the general formula M(MQN)X2 were prepared where the metal ion was Co(II), Ni(II), Fe(II), Cu(II), and Mn(II). The ligands 2-(N-piperidinylmethyl)-3-quinuclidinone (PQN) and 2-(N-dimethylaminomethyl)-3-quinuclidinone (DQN) were prepared along with the analogous cobalt(II) chloride complexes. The series of complexes Co(MQN)X2 where X = Cl, Br, or I were prepared, and magnetic susceptibilities and spectral data obtained. They have room temperature magnetic moments in the range 4.66-4.85 with slight decreases at lower temperatures. Spectral parameters derived from their electronic absorption spectra are typical of tetrahedrally coordinated Co(II) ions with Dq varying between 390-430 cm−1 in the solid phase. Band assignments corresponding to spin-allowed d-d transitions were made. Properties of Co(MQN)Cl2, Co(PQN)Cl2, and Co(DQN)Cl2 show distortion from tetrahedral symmetry in the order MQN PQN