Reactions of the homoleptic acetonitrile complexes of palladium and platinum with diethylamine

The homoleptic [M(MeCN)4]2+ cations (M = Pd, Pt) as the tetrafluoroborato derivatives were reacted with NHEt2. The platinum species affords the amidino derivative {Pt[(E)-HNC(NEt2)Me]4}[BF4]2, 1, as the only detected product of the addition of the amine to the coordinated nitrile. On the contrary, for [Pd(MeCN)4][BF4]2 competition between the substitution of the nitrile and addition of the amine to the nitrile group is operative: by carrying out the reaction in acetonitrile as solvent, complete conversion was obtained to the crystallographically defined {Pd[(E)-HNC(NEt2)Me]4}[BF4]2. Consistent with these findings, PdCl2(MeCN)2 reacts with NHEt2 in acetonitrile yielding the substitution complex PdCl2(NHEt2)2, whereas the amidino complex cis-PtCl2[(E)-HNC(NEt2)Me]2, 3 was obtained from PtCl2(MeCN)2. Complex 3 was characterized by X-ray diffractometry.

Graphical abstractThe amidino derivatives {M[(E)-HNC(NEt2)Me]4}[BF4]2 (M = Pd, Pt) have been obtained reacting the homoleptic [M(MeCN)4]2+ cations with NHEt2. Furthermore, PdCl2(MeCN)2 reacts with NHEt2 in acetonitrile yielding the substitution complex PdCl2(NHEt2)2, at variance with PtCl2(MeCN)2 which yields the already known amidino complex cis-PtCl2 [(E)-HNC(NEt2)Me]2.PdCl2(MeCN)2+2NHEt2→PdCl2(NHEt2)2+2MeCN[Pd(MeCN)4][BF4]2+4NHEt2→[Pd[NHC(NEt2)Me]4][BF4]2Figure optionsDownload full-size imageDownload as PowerPoint slide