Fusing pyrene and ferrocene into a chiral, redox-active triangle

Abstract

A macrocycle that integrates three ferrocene-pyrene dyads in a triangular C2-symmetric arrangement is synthesised as a racemate in a simple one-pot approach. Crystal structural analysis reveals two enantiomeric conformers that...

Development and Characterisation of Highly Conjugated Functionalised Ferrocenylene Macrocycles

“…As mentioned, we were also keen to investigate the synthesis of functionalised macrocycles containing a biferrocene motif [75] . For this we attempted to prepare a pyridyl‐based macrocycle using Ullmann‐like coupling conditions that have previously been developed within our group [75,86] . To this end, the linear tri‐ferrocenylene molecule, 2 , was stirred in the presence of an excess of CuTc, under high dilution, in NMP (Scheme 3).…”

“…[75] For this we attempted to prepare a pyridyl-based macrocycle using Ullmann-like coupling conditions that have previously been developed within our group. [75,86] To this end, the linear tri-ferrocenylene molecule, 2, was stirred in the presence of an excess of CuTc, under high dilution, in NMP (Scheme 3). Analysis of the 1 H-NMR spectrum of the crude reaction mixture revealed the presence of two novel ferrocenecontaining molecules, thought to be the desired macrocycle, 4, and the hydrodehalogenation product, 4 a.…”

“…However, a number of groups have previously reported the successful isolation of ferrocene-containing macrocycles which could be considered as highly conjugated. [73][74][75][76][77][78][79][80][81][82][83][84][85][86][87] For example, previous works have studied the synthesis of molecules which contain direct CÀ C connections between ferrocene units in the synthesis and isolation of a limited number of biferrocenylene, triferrocenylene and higher-order macrocycles, albeit in low-yields. [73,74,[77][78][79][80][81][82] Other groups have utilised longer carbon-based chains to form connections between ferrocene units.…”

“…Unfortunately, relatively few studies have reported the synthesis of highly conjugated ferrocenylene macrocycles, due to complexities associated with the synthesis of these systems, such as rotation around the ferrocene unit, and the need for cross‐coupling methodologies, which often lead to competitive side‐reactions. However, a number of groups have previously reported the successful isolation of ferrocene‐containing macrocycles which could be considered as highly conjugated [73–87] …”

Ferrocenyl-Substituted Triazatruxenes: Synthesis, Electronic Properties, and the Impact of Ferrocenyl Residues on Directional On-Surface Switching on Ag(111)

“…Despite the importance and advantageous properties of both ferrocenes and PAAs, only a few examples of coupled redox systems that combine both types of constituents were reported. , The direct connection between the five-membered Cp and the six-membered phenyl rings of the TAT framework allows for their rather coplanar arrangement, similar to what is seen for aryl-substituted ferrocenes. – Small torsions at these linkages are highly advantageous for on-surface deposition and STM studies . From a chemist’s viewpoint, Fc-appended TATs are also of interest with regard to their rich redox chemistry.…”