Bi- and trimetallic rare-earth–palladium complexes ligated by phosphinoamides

Abstract

The synthesis of the heterometallic early-late 4d/4f bi- and trinuclear phosphinoamido Ln-Pd(0) complexes [(Ph2PNHPh)Pd{μ-(Ph2PNPh)}3Ln(μ-Cl)Li(THF)3] (Ln = Y, Lu) and [Li(THF)4][{(Ph2PNHPh)Pd}2{μ-(Ph2PNPh)}4Ln] (Ln = Y, Lu) is described. The latter compounds are the first early-late trimetallic phosphinoamido complexes. Although the metal atoms are forced into close proximity by the phosphinoamido ligands, quantum chemical calculations show only weak metal-to-metal interactions.

Early–Late Heterometallic Complexes of Gold and Zirconium: Photoluminescence and Reactivity

“…At large distances, the model complex dissociates into the expected units composing of highly ionic Cp 2 ZrF 2 and two [(PMe 3 )AuCl] molecules (the potential energy curve is given in Figure S1 of the Supporting Information). Comparable to the Lu/Pd system reported before, the long‐range interaction shows R −2 behaviour, which is typical for a charge–dipole interaction. Due to our understanding of the Lu/Pd system, we interpret the bonding between Zr and Au in 6 to be comparably weak…”

“…The synthesis of heterometallic ELHBs usually requires ligand systems which take the different affinities of the metals for certain donor atoms into account. Typically, soft donor centres (phosphines, NHCs or thiolates) are combined with hard donor centres (alkoxides, amidinates) on a common backbone . Another possibility is the synthesis of a mono‐ or polynuclear complex which can function as a metalloligand for the coordination of other metals .…”

“…Typically,s oft donor centres (phosphines, NHCs or thiolates) are combinedw ith hard donor centres (alkoxides, amidinates) on ac ommon backbone. [11][12][13][14] Another possibility is the synthesis of am ono-o rp olynuclear complex which can function as am etalloligand for the coordinationo fo ther metals. [6,[15][16][17][18][19][20] This approach could also be used to synthesize ELHBs of gold andz irconium and this particular combination of metals is attractive with regard to the photophysicalp roperties of the resulting complexes.G old(I) compounds often display interesting photoluminescence( PL) behaviour, [21][22][23][24][25] which can be significantly influenced by intermetallic interactions [12] in polynuclear gold compounds.…”

A Scandium Metalloligand‐Based Heterobimetallic Pd−Sc Complex: Electronic Tuning Through a Very Short Pd→Sc Dative Bond

“…Heterobimetallic Pd−Ln complexes have recently been reported for yttrium and lutetium, but the scandium congener has hitherto been unknown. The reported Pd−Y and Pd−Lu distances were 2.98–3.18 Å and 2.97 Å, respectively, longer than that in 2 if the different ionic radii of Sc 3+ (0.745 Å), Y 3+ (0.900 Å), and Lu 3+ (0.861 Å) are considered . The short Pd−Sc distance in 2 can be attributed to the very low coordination number at the Lewis acidic Sc 3+ , withdrawing electron density from the Lewis basic Pd 0 center for stability.…”

“…Recent studies have shown that phosphinoamido and phosphine‐functionalized amido ligands can support LM−Ln bonding interactions. Although only weak interactions are involved in the case of the complex shown in Figure d, stronger Ni→Lu interactions have been shown to influence catalytic activity by varying the coordination sphere of the Lu 3+ center (Figure e) …”