An unexpected triammine(oxalato)platinum(II) complex obtained from the aqueous solution of tetraammineplatinum(II) oxalate

Abstract

An unexpected complex, triammine(oxalato)platinum(II) in which oxalate anion acts as a monodentate ligand, was isolated in the process of recrystallizing [Pt(NH 3 ) 4 ](C 2 O 4 ). The complex was presumably formed via the loss of one ammonia molecule from [Pt(NH 3 ) 4 ](C 2 O 4 ), followed by the binding of oxalate from the outer coordination sphere. Single crystal X-ray diffraction study revealed that the Pt(II) atom was coordinated on a distorted square by three N atoms of the ammine molecules and one O atom of the oxalate ligand. The crystal packing was stabilized by moderate to strong hydrogen bonds formed between ammine, water molecules and O atoms of oxalate with d(NÁÁÁO) in the range of 2.84(2)-3.29(2) Å , and d(OÁÁÁO) in the range of 2.86(2)-3.37(2) Å . The complex underwent thermal decomposition at 200-231°C in the nitrogen atmosphere, giving rise to Pt, NH 3 and CO 2 .

A Novel Pd Precursor Loaded γ‐Al2O3 with Excellent Adsorbent Performance for Ultra‐Deep Adsorptive Desulfurization of Benzene

“…In an aqueous solution, the complex dissociates into NH 4+ and the coordination anion [Pd(NO 2 ) 2 (C 2 O 4 )] 2− , which can be detected using electrospray ionization–mass spectroscopy (ESI‐MS) at m/e = 140 (Figure S3, Supporting Information). [ 25,26 ] The atomic weight of Pd corresponds to 104 Pd, a naturally stable isotope. The results show that the synthesized Pd complex had the chemical structure of (NH 4 ) 2 [Pd(NO 2 ) 2 (C 2 O 4 )]·nH 2 O.…”

“…In an aqueous solution, the complex dissociates into NH 4+ and the coordination anion [Pd(NO 2 ) 2 (C 2 O 4 )] 2− , which can be detected using electrospray ionization-mass spectroscopy (ESIMS) at m/e = 140 (Figure S3, Supporting Information). [25,26] The atomic weight of Pd corresponds to 104 2− ions that coordinate with Pd 2+ decompose, and the remaining Pd 2+ is anchored on the surface of alumina because of strong interactions with γ Al 2 O 3 to form PdOAl. Because the target complex has more and larger ligands than other precursors, the mutual repulsion between complexes makes Pd highly dispersed on the surface of Al 2 O 3 .…”

Synthesis and Thermo-chemical Profile of [Pt(NH3)4]C2O4 and [Pt(NH3)4](OOCCH2COO) as New Precursors for Supported Platinum Catalysts

“…[Pt(NH3)4](C2O4) was synthesized by using the process described in our previous work 18 but with some improvements. Briefly, cis-[Pt(NH3)2I2] (50 g, 103 mmol) was mixed with a 200 mL solution of silver nitrate (34.82 g, 205 mmol) and stirred at 55 ºC for about 10 h until no free silver ions could be detected by the precipitation reaction with NaCl.…”

Ni-Catalyzed Protecting Group Free Diphenic Acid Analog Synthesis

“…14 The ligand exchange between Pt-1 complexes and [1,1′-biphenyl]-2,2′-dicarboxylate occurred when they were mixed in ddH 2 O in the presence of AgNO 3 , delivering the desired new Pt-2 in 66% to 94% yield. 15 It is worth noting that the Pt-2 complexes with different functional groups, including cyclobutyl (Pt-2a), trifluoromethyl (Pt-2b), the thiophene group (Pt-2c), and the diamine ligands ranging from cyclohexane-1,2-diamine (Pt-2a∼c) to ethane-1,2-diamine (Pt-2d), benzene-1,2-diamine (Pt-2e), and ammonium (Pt-2f) were adopted to prepare Pt(II) agents.…”

“…As presented in Figure , diphenic acid analogs were first deprotonated using KO t -Bu to give potassium [1,1′-biphenyl]-2,2′-dicarboxylate in quantitative yields in THF at room temperature, and Pt- 1 complexes were prepared from K 2 PtCl 4 and corresponding diamines in high yields from 80% to 93% . The ligand exchange between Pt- 1 complexes and [1,1′-biphenyl]-2,2′-dicarboxylate occurred when they were mixed in ddH 2 O in the presence of AgNO 3 , delivering the desired new Pt- 2 in 66% to 94% yield . It is worth noting that the Pt- 2 complexes with different functional groups, including cyclobutyl (Pt- 2a ), trifluoromethyl (Pt- 2b ), the thiophene group (Pt- 2c ), and the diamine ligands ranging from cyclohexane-1,2-diamine (Pt- 2a ∼ c ) to ethane-1,2-diamine (Pt- 2d ), benzene-1,2-diamine (Pt- 2e ), and ammonium (Pt- 2f ) were adopted to prepare Pt­(II) agents.…”