New rhenium(III) semiclathrochelates with biorelevant apical substituents: Synthesis, X-ray structure and reactivity

摘要: Abstract One-pot reduction–condensation of K2ReCl6, dimethylglyoxime and phenylboronic acid anhydride in the presence metallic silver gave mixture boron-capped tris-dioximate rhenium(III) semiclathrochelate with its reduced diimine-iminoximate derivatives, resulted from side ligand-centered domino-reaction; one them was characterized by single crystal X-ray diffraction. Its cation coordinates two boron-bridged iminooximate moieties non-bridged imine chelate ligand. Third oxygen atom boron-containing bridging fragment is also coordinated to this ion, thus giving a capped trigonal-prismatic (TP) ReN6O‐ coordination polyhedron which Re–O distance substantially smaller than Re–N ones {1.966(8) 2.029(11)–2.099(11) A, respectively}. Template condensation ReCl3((C6H5)3P)2(CH3CN) cyclohexane-1,2-dione dioxime (nioxime) 3-formylphenylboronic afforded formyl-terminated tris-nioximate, undergoing further H+-catalyzed isoniazid give hydrazone apical functionalizing vector substituent. As follows diffraction data, ReN6Cl‐ former complex possesses geometry TP distortion angle φ equal 5.0° Re–Cl (2.4040(9) A) that greater (2.046(3)–2.127(3) A). The attempted capping formylphenylboron IGe(CF3)3 transmetallation, leading germanium-capped semiclathrochelate. analogous semiclathrochelates hexadecyl cholesteryl groups were prepared using direct template nioxime hexadecylboronic on ion as matrix, non-macrocyclic tris-nioximate cholesterylboronic acid, respectively.