To prepare N2-derived cationic boryldiazenido-tungsten complexes as models of semimetallic metal-borinium frustrated Lewis pairs activating N2, we have attempted halide abstraction from trans-(diarylboryl)diazenido-halo-tungsten complexes. Reactions with Tl+ led to adducts in which coordination of the cation differs depending on the boryldiazenide substituents and the ancillary ligand. Chloride scavenging was not observed.