Structures and Magnetic Properties of Group 13 Metal Tris‐ O ‐benzosemiquinonato Complexes

New tris-o-benzosemiquinonato complexes of Al, Ga, and In based on the sterically hindered o-benzoquinone 5,8-di-tert-butyl-2,3-dihydro-1,4-ethanoquinoxaline-6,7-dione (NN-3,6-Q) were synthesized. The structures of the hexacoordinate metal compounds were investigated by X-ray diffraction. The magnetic properties of the complexes obtained were found to be strongly dependent on their molecular geometry. The octahedral Al and Ga derivatives demonstrate ferromagnetic exchange between the magnetic centers, whereas the trigonal-prismatic In complex shows an antiferromagnetic coupling.