Influence of the Substituent's Size in the Phosphinate Group on the Conformational Possibilities of Ferrocenylbisphosphinic Acids in the Design of Coordination Polymers and Metal-Organic Frameworks.

This paper illustrates how the size and type of substituent R in the phosphinate group of ferrocenyl bisphosphinic acids can affect conformational possibilities and coordination packing. It also demonstrates that H-phosphinate plays a key role in variational mobility, while Me- or Ph- substituents of the phosphinate group can only lead to 0D complexes or 1D coordination polymer. Overall, this paper provides valuable insights into the design and construction of coordination polymers based on ferrocene-contained linkers. It sheds light on how different reaction conditions and substituents can affect conformational possibilities and coordination packing, which could have significant implications for developing new polymers with unique properties.

Synthesis, Structure, and Electrochemical Properties of 2,3,4,5-Tetraphenyl-1-Monophosphaferrocene Derivatives.

Heteroleptic 2,3,4,5-tetraphenyl-1-monophosphaferrocene [FeCp(η5-PC4Ph4)] was obtained at a 62% yield through the reaction of lithium 2,3,4,5-tetraphenyl-1-monophosphacyclopentadienide Li(PC4Ph4) (1) with [FeCp(η6-C6H5CH3)][PF6]. The structure of 1-monophosphaferrocene 2 and its W(CO)5-complex 3 were confirmed by multinuclear NMR and single-crystal X-ray diffraction study and further supported by DFT calculations. Cyclic voltammetry demonstrated that [FeCp(η5-PC4Ph4)] 2 has a quasi-reversible oxidation wave. The comparison of the properties of phosphaferrocene 2 with those of W(CO)5-complex 3 shows the possibility of changing the coordination type during oxidation.

Synthesis and electrochemical properties of 3,4,5-tris(chlorophenyl)-1,2-diphosphaferrocenes.

A novel representative of sodium 3,4,5-triaryl-1,2-diphosphacyclopentadienide containing a chloro substituent in the meta-position of the aryl groups was obtained with a high yield based on the reaction of tributyl(1,2,3-triarylcyclopropenyl)phosphonium bromide and sodium polyphosphides. Further reaction of sodium 3,4,5-tris(3-chlorophenyl)-1,2-diphosphacyclopentadienide with [FeCp(η6-C6H5CH3)][PF6] complex gives a new 3,4,5-tris(3-chlorophenyl)-1,2-diphosphaferrocene. The electrochemical properties of 3,4,5-tris(3-chlorophenyl)-1,2-diphosphaferrocene were studied and compared to 3,4,5-tris(4-chlorophenyl)-1,2-diphosphaferrocene. It was found that the position of the chlorine atom on the aryl fragment has an influence on the reduction potential of 1,2-diphosphaferrocenes, while the oxidation potentials do not change.

Comparison of crystal structure and DFT calculations of triferrocenyl trithiophosphite's conformance.

A triferrocenyl trithiophosphite was studied by X-ray single-crystal diffraction. Triferrocenyl trithiophosphite has nine axes of internal rotation: three P-S bonds, three C-S bonds and three Fe-cyclopentadienyl axes. Rotation around the P-S bonds results in a totally asymmetric structure with three ferrocenylthio groups exhibiting different orientations towards the phosphorus lone electron pair (LEP). A comparison of DFT calculations and X-ray diffraction data is presented, herein we show which conformations are preferred for a given ligand.

Synthesis, structure, and electrochemical properties of 4,5-diaryl-1,2,3-triphosphaferrocenes and the first example of multi(phosphaferrocene).

The reaction between aryl substituted sodium 1,2,3-triphospholides or disodium bis(1,2,3-triphospholide) and [Fe(η6-(C6H5CH3)Cp]+[PF6]- in boiling diglyme results in pure 1,2,3-triphosphaferrocenes 1-3 or bis(1,2,3-triphosphaferrocene) 4, respectively, in good yields. The structure of all obtained 1,2,3-triphosphaferrocenes 1-4 has been extensively studied experimentally (NMR, UV-Vis spectroscopy, and X-ray analysis for 1 and 4) and quantum chemically. The electrochemical properties of 1,2,3-triphosphaferrocenes 1-4 in the solid state were studied for the first time and a reversible one-electron oxidation (E1/2 = 0.52-0.92 V vs. Fc+/Fc) was demonstrated for 1, 3, and 4. In the case of 1,4-bis(5-phenyl-4-(1,2,3-triphospaferrocenyl))benzene 4, consecutive oxidation in the solid state is observed in contrast to other 1,2,3-triphosphaferrocenes 1-3. According to the ESR data, the g-factor of the oxidized bis(1,2,3-triphosphaferrocene), 4 (g = 2.12) is different from the g-factors of oxidized 1,2,3-triphosphaferrocenes 1-3 (g = 2.01). This is the first example of multi(ferrocenyl) systems based on the phosphaferrocene motif, which in turn opens up a new fundamental platform for the preparation of compounds with stimuli-responsive properties.

Synthesis and magnetic properties of manganese carbonyl complexes with different coordination modes of 3,4,5-triaryl-1,2-diphospholide ligands.

The set of complexes bis-(µ:η(1),η(1)-3,4,5-triaryl-1,2-diphosphacyclopentadienyl)-bis-(tetracarbonyl manganese(i)) (aryl = C6H5 (), p-FC6H4 (), p-ClC6H4 ()) undergo an irreversible rearrangement to mononuclear 3,4,5-triaryl-1,2-diphosphacymantrenes (). According to quantum-chemical calculations binuclear complexes can be considered to be products of kinetic control and mononuclear species are thermodynamically favorable compounds. The antiferromagnetic intramolecular interaction observed for complexes can be effectively tuned by using substituents in the para-position of the arene ring, whereas mononuclear 1,2-diphosphacymantrenes are diamagnetic.