Cobalt complexes of a selenium diimide and a tellurium diimide dimer

[CoCl2{N,N′-Te2(NtBu)4}] (1) was obtained in good yields by the reaction of equimolar amounts of (tBu)NTe(μ-NtBu)2TeN(tBu) and CoCl2 in toluene under an argon atmosphere. The crystal structure of 1·CH2Cl2 showed that the dimeric tellurium diimide ligand is N,N′-chelated to cobalt. The related reaction of Se(NtBu)2 and CoCl2 affords a green product tentatively identified as a 1:1 adduct [CoCl2{N,N′-Se(NtBu)2}] (CHN analysis). However, recrystallization from thf produces the ion-separated complex [Co2(μ-Cl)3{N,N′-Se(NtBu)2}2(thf)2][CoCl3{NH2(tBu)}]·1½thf (2·1½thf), in which the monomeric selenium diimide ligand is N,N′-chelated to cobalt in the cation. A pathway for the formation of 2 from [CoCl2{N,N′-Se(NtBu)2}] in thf is proposed.

Graphical abstract[CoCl2{N,N′-Te2(NtBu)4}] (1) was obtained in good yields by the reaction of equimolar amounts of (tBu)NTe(μ-NtBu)2TeN(tBu) and CoCl2 in toluene under an argon atmosphere. The related reaction of Se(NtBu)2 and CoCl2 affords a green product that upon recrystallization from thf produces the ion-separated complex [Co2(μ-Cl)3{N,N′-Se(NtBu)2}2(thf)2][CoCl3{NH2(tBu)}]·1½thf (2·1½thf).Figure optionsDownload full-size imageDownload as PowerPoint slide