827623-80-3Relevant academic research and scientific papers
Synthesis of a library of iridium-containing dinuclear complexes with bridging PNNN and PNNP ligands (BL), [LM(μ-BL)M′L′]BF 4. 1. Specific synthesis of isomeric heterodinuclear complexes with switched metal arrangements
Dubs, Christian,Yamamoto, Toshiki,Inagaki, Akiko,Akita, Munetaka
, p. 1344 - 1358 (2008/10/09)
Specific synthesis of a series of Ir-containing homo- and heterodinuclear complexes with the PNNP (3,5-bis((diphenylphosphino)methyl)pyrazolato) and PNNN ligands (3-(diphenylphosphino)methyl-5-pyridylpyrazolato) is reported. Reaction of the PNNX-H precursors (X = P, N) with [Ir(cod)2]BF4 gives pale yellow precipitates, which are characterized as the cyclic dimers of the 1:1 adduct, [μ-K1(P): κ2(AyO-PNNX-H)Ir(cod)] 2(BF4)2 (X = P, N). In the case of the PNNN system, subsequent sequential treatment of the 1:1 adduct with NEt3 and a second metal reagent ([M(L)(cod)]BF4: M(L) = Rh(cod), Pd(allyl)) (reaction 1) gives [(cod)Ir(PNNN)M(L)]BF4, whereas the reversed addition of the reagents (reaction 2) furnishes [(L)M(PNNN)Ir(cod)]BF 4, the regioisomer with the switched metal arrangement. Selective preparation of the heterodinuclear PNNP complexes [(cod)Ir(PNNP)M(L)]BF 4 requires the addition according to reaction 1. In reaction 1 of the 1:1 dinuclear adduct of the PNNN system, deprotonation of the N-H part triggers interligand migration of the Ir(cod) fragment from the N,N site of one ligand to the P,N site of the other ligand to give [(cod)Ir(PNNN)]BF4, which reacts with the second metal fragment at the N,N site to furnish [(cod)Ir(PNNN)M(L)]BF4. On the other hand, reaction 2 involves dissociation of the dinuclear species into the mononuclear N,N-coordinated one, [(PNNN-H)Ir(cod)]BF4, and subsequent interaction at the free P moiety followed by deprotonation and coordination gives the other regioisomer. These intriguing transformations result from the unique coordination properties of Ir (cationic vs neutral, hard vs soft, 5- vs 4-coordination, N,N vs P,N chelation), which are controlled by the deprotonation-protonation procedure. As a result of the present study, a library for Ir-containing homo- and heterodinuclear Ir(I) complexes with the PNNP and PNNN ligands has been constructed.
Selective synthesis of isomeric heterodinuclear complexes with switched metal arrangements via proton-induced reversible metal migration
Dubs, Christian,Inagaki, Akiko,Akita, Munetaka
, p. 2760 - 2761 (2008/10/09)
Pairs of isomeric heterodinuclear complexes, [(cod)Ir(μ-PNNN)M(L)] BF4 and [(L)M(μ-PNN)Ir(cod)]BF4, with switched metal arrangements are prepared in a specific manner by simply changing the addition order of the reagents.
