Electrochemically driven molecular rotors based on ferrocene-1,1'-diyl-bisphosphinic acids

Ferrocene-containing non-interlocked molecular machines

“…Deprotonation causes the system to switch back to its initial anti state. Similar protonationdriven ferrocene-based switches have been developed by Higuchi et al 22d and Milyukov et al, 41 using amines and phosphinic acids as the protonatable groups, respectively.…”

Ferrocene and Transition Metal Bis(Dicarbollides) as Platform for Design of Rotatory Molecular Switches

“…Recently 1,1′-ferrocene diphosphinic acids were proposed as similar proton-driven switchers [ 25 ]. In the neutral, fully protonated form, the eclipsed cis -conformation (rotation angle is 1.5°) is stabilized by two intramolecular hydrogen bonds between the phosphinic groups.…”

Evidence of extremely short hydrogen bond in the homoconjugated ferrocene-1,1′-diyl-bisphosphinic acid anion: sign change of the H/D isotope effect on the 31P NMR chemical shift

“…monoanion " dianion transition. [17][18][19] Besides, the conformational manifold of intra-and intermolecular hydrogen bonding patterns of Fc(P(R)OOH) 2 in conjunction with the substituent size in the phosphinate group have proven to be paramount for the coordination properties of Fc(P(R)OOH) 2 in novel coordination polymers and metal-organic frameworks with tunable optical, magnetic and redox properties. [20][21][22][23][24] Separate interest is drawn toward H-bonded complexes formed solely by Fc(P(R)OOH) 2 .…”