Two New Nitronyl Nitroxide Radicals and Their Complexes with M(hfac)2 [M=Co(II), Ni(II), Mn(II)]: Syntheses, Crystal Structures, and Magnetic Characterizations

Two new nitronyl nitroxides with amido units L1 and L2 were synthesized and characterized. Reactions of L1 and L2 with M(hfac)2 [hfachexafluoroacetylacetonate, MCo(II), Ni(II), Mn(II)] afforded five hetero‐spin complexes L1Co(hfac)2, L1Ni(hfac)2, L2Co(hfac)2, L2Ni(hfac)2 and L2Mn(hfac)2. The crystal structures and magnetic characterizations of L1, L2 and their metal complexes LM(hfac)2 were described and discussed. Crystal structural analysis shows that both the carbonyl oxygen and the nitroxide oxygen are coordinated to the metal ions. Strong antiferromagetic coupling between the nitronyl nitroxides and metal ions were observed for all the five LM(hfac)2 complexes.