The rearrangement of phosphitohydrazide ligand [(ArO)2P–NPh–NPh–] into iminophosphoranate anion [(PhNdouble bond; length as m-dashP(OAr)2–NPh–] {(ArO)2P = [CH2(tBuMeC6H2O)2P]} in coordination sphere of divalent cobalt

The reaction of bromophosphite (ArO)2PBr {(ArO)2P = CH2(6-tBu-4-Me-C6H2O)2P} with lithium salt of 1,2-diphenylhydrazine gave phosphitohydrazine (ArO)2P–NPh–NPhH (2) in 64% yield. The last one reacted with Co[N(SiMe3)2]2 to afford cobalt(II) iminophosphoranate (PhNdouble bond; length as m-dashP(OAr)2–NPh–)2Co (3), which is the result of isomerisation of the phosphitohydrazide ligand in coordination sphere of divalent cobalt.