Two mononuclear U02(VI) complexes of the general formula [(HL)U02(OH2)2] О.бШО, where L is a pentadentate N2O3 asymmetric Schiff base ligand, were synthesized and used as ligands for further coordination of either Cu(II) or Ni(II) ions. The U02(VI) ion occupies the outer O2O sites of the ligands, thus leaving the inner N2O2 sites of the ligands vacant for further coordina­ tion. Different types...

We have investigated the molecular geometries of a series of dicoordinated d(10)-transition-metal complexes ML2 (M=Co(-), Rh(-), Ir(-), Ni, Pd, Pt, Cu(+), Ag(+), Au(+); L=NH3, PH3, CO) using relativistic density functional theory (DFT) at ZORA-BLYP/TZ2P. Not all complexes have the expected linear ligand-metal-ligand (L-M-L) angle: this angle varies from 180° to 128.6° as a function of the metal...

Over the last 2 decades, the rapid development of new synthetic routes for the preparation of expanded porphyrin macrocycles has allowed for the exploration of a new frontier consisting of "porphyrin-like" coordination chemistry. In this Account, we summarize our exploratory forays into the still relatively poorly explored area of oligopyrrolic macrocycle metalation chemistry. Specifically, we ...

Murexide, a reddish purple compound has the structure shown in Fig. 1. It has received much interest because of its application in chemical analysis and spectrophotometric fields [1, 2]. It is considered as the ammonium salt of purpuric acid and named as ammonium 2,6-dioxo-5-(2,4,6-trioxo-tetrahydro-pyrimidine-5-ylidene amino)-1,2,3,6-tetrahydro-pyrimidine-4-olate. It serves as a metal ion indi...