Darstellung und Ligandeneigenschaften eines 1.2.5-Azadiborolen-Derivates [1] / Synthesis and Ligand Properties of an 1,2,5-Azadiborolene Derivative [1]

3,4-Diethyl-1,2,5-trimethyl-1,2,5-azadiborolene (3) is obtained from 3,4-diethyl-2,5-dimethyl-1,2,5-thiadiborolene (1) and heptamethyldistannazan. The Lewis-acidic π4 ligand (3) forms the transition metal complexes 5, 6, 7 and 8, when reacted with Fe2(CO)9, (C5H5)CO(CO)2, Ni(CO)4 and Co2(CO)8, respectively. The properties of 5-8 are compared with those of the corresponding thiadiborolene complexes. In contrast to 1 the azadiborolene ligand does not favor the formation of tripledecker complexes