Phosphorus guiding palladium: [4 + 4] metallomacrocyclic Pd II complex and self-assembly of heterometallic Pd II /Zn II grid-type complex.

The reaction of heteroditopic ligand 1 featuring a hard pyridine-hydrazone-pyrimidine (N,N,N) site and a softer pyrimidine-hydrazone-phosphane (N,N,P) pocket with [Pd(CH 3 CN) 4 ](OTf) 2 in different metal-to-ligand ratios (M : L) gave the homobimetallic Pd II complex [Pd 2 (1)(CH 3 CN) 2 ](OTf) 4 (2, M : L ratio 2 : 1), the [4 + 4] metallomacrocyclic Pd II complex [Pd(1)] 4 (OTf) 8 (3, M : L ratio 1 : 1) and the monometallic complex [Pd(1) 2 ](OTf) 2 (4, M : L ratio 1 : 2). The soft N,N,P pocket preferably coordinates Pd II , while the harder N,N,N coordination site selectively binds Zn II forming the homoleptic meridional "corner" complexes [Zn(1) 2 ](OTf) 2 (5) and [Pd 2 Zn(1) 2 ](OTf) 6 (6). The distinctive coordination behavior of ligand 1 is highlighted by the self-assembly of the heterometallic Pd II /Zn II grid-type complex [Pd 2 Zn 2 (1) 2 ](OTf) 8 (7) in a one-pot reaction. Complexes 2-7 were characterized by mass spectrometry, UV/Vis and NMR spectroscopy including DOSY NMR, and single-crystal X-ray diffraction studies were performed for 2-4 and 7.