Terminal pentafluorobenzimidoylpalladium(II) complexes. X-ray structure of trans-[Pd{C(C6F5)NMe}Cl(CNMe)2]

The preparations of the complexes trans-[Pd{C(C6F5)N(R1)}Cl(CNR2)2] and [Pd{C(C6F5)N(R1)}(CNR2)2]X (R1 = Me, p-Tol; R2 = Me, p-Tol, But; X = ClO4 or BPh4) from [Pd2{μ-C(C6F5)N(R1)}2Cl2(CNR2)2] are described. The splitting of the imidoyl bridges is accompanied by an isomerization of the imidoyl group from the syn to the anti conformation as shown by a single crystal X-ray diffraction study of trans-[Pd{C(C6F5)N(Me)}Cl(CNMe)2]. Attempted preparations of [Pd{C(C6F5)=N(R1)}Cl(PPh3)2] from [Pd2-C(C6F5)N(R1)}2Cl2(PPh3)2] led to elimination of CNR and formation of trans-[Pd(C6F5)Cl(PPh3)2]; this is the first example of isonitrile elimination in palladium chemistry.