Synthesis of Ruthenium Complexes Bearing PCP-Type Pincer Ligands and Their Application to Direct Synthesis of Imines from Amines and Benzyl Alcohol

Abstract

Ruthenium complexes bearing N-heterocyclic carbene-and phosphine-based PCP-type pincer ligands are synthesized and characterized by X-ray crystallography. The ruthenium− PCP complexes have catalytic activity toward direct synthesis of imines from reactions of amines and benzyl alcohol. The lifetime of the ruthenium complex bearing the PCP pincer ligand is longer than that of the ruthenium complex bearing a pyridine-based PNPtype pincer ligand.

Transition Metal Complexes Supported by N‐Heterocyclic Carbene‐Based Pincer Platforms: Synthesis, Reactivity and Applications

“…The metalation of 125 a was studied by the same group, and a series of pincer complexes (131-137) of Ni, Rh, Ir and Ru were obtained (scheme 42). [59,60,61] For most cases, a strong base KN(SiMe 3 ) 2 was employed to prepare the free carbene, which underwent subsequent metalation. In contrast, pincer hydrido complexes 133 and were synthesized via an oxidative addition approach.…”

A Germylene Supported by Two 2‐Pyrrolylphosphane Groups as Precursor to PGeP Pincer Square‐Planar Group 10 Metal(II) and T‐Shaped Gold(I) Complexes

“…[1,2] As strong electrondonating ligandsa re frequently required to preparec atalytically efficient metal complexes,m any pincerl igandsh aving an Nheterocyclic carbene (NHC) as the central C-donor grouph ave already been reported. [3] However,a lthough the heavier carbene analogues (silylenes, germylenes, and stannylenes) are also very strong electron-donating groups [4] ands ome of them have already demonstrated an excellent ligand behavior in catalytic reactions, [5,6] their participation in (or as precursors of) pincerc omplexes is still limited to very few ECE, [6k,l, 7] ENE, [6d,h,i,j, 7d] NEN, [7b,c] and PEP [8][9][10][11][12] systems (E = Si, Ge, or Sn). Regarding metal-free PGeP pincer-type germylenes,o nly two specimens have so far been reported, namely,G e-(NCH 2 PtBu 2 ) 2 C 6 H 4 [11] and Ge(NC 6 H 4 PPh 2 ) 2 C 2 H 4 [12] (compounds A and B in Figure 1) and their transition-metal derivative chemistry has just started to be developed.…”

Bulky PNP Ligands Blocking Metal-Ligand Cooperation Allow for Isolation of Ru(0), and Lead to Catalytically Active Ru Complexes in Acceptorless Alcohol Dehydrogenation

“…The X-ray structure of complex 2 was published previously. 8 Detailed information about crystal structure determination can be accessed via supplementary cif files. The crystallographic data for the investigated compounds have been deposited in the Cambridge Crystallographic Data Centre and Fachinformationszentrum Karlsruhe Access Structures service as supplementary publication deposition numbers 2079124-2079134, 2079338.…”