First paramagnetic PdII complex with a PdN4S2 coordination core

Abstract

Reaction of the potassium salt of N-thiophosphorylated thiourea 2-PyNHC(S)NHP(S)(OiPr)₂ (HL) with PdCl₂ in aqueous MeOH leads to the formation of two mononuclear homoleptic complexes [Pd{2-PyNHC(S)NP(S)(OiPr)₂-1,5-S,S′}₂] ([Pd(L-1,5-SS,SS′)₂2]) and [Pd{2-PyNHC(S)NP(S)(OiPr)₂-1,5,7-N,N′,S}₂] ([Pd(L-1,5,7-NN,NN′,SS)₂2]), while the mechanically induced solid-state reaction of KL and PdCl₂ leads to the exclusive formation of [Pd(L-1,5,7-NN,NN′,SS)₂2]. The dithiocoordinated desmotrope is square-planar and diamagnetic, while the second desmotrope is unprecedentedly octahedrally configured and paramagnetic.