[E(μ-NBbp)]2 (E = P, As) - group 15 biradicals synthesized from acyclic precursors.

The synthesis of Bbp stabilized biradicals of the type [E(μ-NBbp)]2 (E = P, As) (Bbp = 2,6-bis[bis(trimethylsilyl)methyl]phenyl) was investigated. Contrary to the established synthetic protocol for terphenyl substituted biradicals [E(μ-NTer)]2 by reduction of [ClE(μ-NTer)]2, the analogous Bbp substituted precursor [ClE(μ-NBbp)]2 could only be obtained in low yields. For this reason, a new synthesis had to be found to generate [E(μ-NBbp)]2. Instead of using cyclic [ClE(μ-NBbp)]2 we prepared the acyclic Bbp-N(ECl2)2 species starting from Bbp-NH2 and ECl3 and studied the reduction with magnesium chips, which led to the formation of the desired biradicals [E(μ-NBbp)]2. All species along the reaction path were fully characterized.