Redox-Active Macrocyclic and Linear Oligo-Carbosiloxanes Prepared via Hydrosilylation from 1,3-Divinyl-1,3-Dimethyl-1,3-Diferrocenyldisiloxane

Ferrocene-Containing Conjugated Oligomers Synthesized by Acyclic Diene Metathesis Polymerization

A series of conjugated, symmetrical, and ferrocene-containing main-chain monomers was prepared following a gentle coupling reaction. Ferrocene-containing oligomers with all-trans-configured vinylene bonds could be synthesized via acyclic diene metathesis (ADMET) polymerization. These oligomers had a larger Stokes shift (2400 to 2600 cm⁻¹) and both exhibited stable and reversible electrochemistry. Meanwhile, the copolymerization of 1,1’-bis[1-methyl-2-(4-vinylphenyl)ethenyl]ferrocene with 2,7-divinyl-9,9-dioctylfluorene was achieved. The structurally regular copolymers proved their optical and electrochemical properties. The fluorescence intensity of the copolymer gradually enhanced with the increasing number of fluorene units. At the same time, it was also found that the color of the copolymers had a significant change from yellow-green to red.

Formation of unexpected silicon- and disiloxane-bridged multiferrocenyl derivatives bearing Si-O-CH[double bond, length as m-dash]CH2 and Si-(CH2)2C(CH3)3 substituents via cleavage of tetrahydrofuran and trapping of its ring fragments

The formation of a family of silicon- and siloxane-bridged multiferrocenyl derivatives carrying different functional groups attached to silicon, including Fc₂(CH₃)₃C(CH₂)₂SiCH[double bond, length as m-dash]CH₂ (5), Fc₂(CH₂[double bond, length as m-dash]CH-O)SiCH[double bond, length as m-dash]CH₂ (6), Fc₂(OH)SiCH[double bond, length as m-dash]CH₂ (7), Fc₂(CH₂[double bond, length as m-dash]CH-O)Si-O-Si(O-CH[double bond, length as m-dash]CH₂)Fc₂ (8) and Fc₂(CH₂[double bond, length as m-dash]CH-O)Si-O-SiFc₃ (9) is described. Silyl vinyl ether molecules 6, 8 and 9 and the heteroleptic vinylsilane 5 resulted from the competing metathesis reaction of lithioferrocene (FcLi), CH₂[double bond, length as m-dash]CH-OLi or (CH₃)₃C(CH₂)₂Li with the corresponding multifunctional chlorosilane, Cl₃SiCH[double bond, length as m-dash]CH₂ or Cl₃Si-O-SiCl₃. The last two organolithium species have been likely formed in situ by fragmentation of the tetrahydrofuran solvent. Diferrocenylvinyloxyvinylsilane 6 is noteworthy since it represents a rare example of a redox-active silyl mononomer in which two different C[double bond, length as m-dash]C polymerisable groups are directly connected to silicon. The molecular structures of the silicon-containing multiferrocenyl species 5, 6, 8 and 9 have been investigated by single-crystal X-ray diffraction studies, demonstrating the capture and storage processes of two ring fragments resulting from the cleavage of cyclic THF in redox-active and stable crystalline organometallic compounds. From electrochemical studies we found that by changing the anion of the supporting electrolyte from [PF₆]^- to [B(C₆F₅)₄]^-, the redox behaviour of tetrametallic disiloxane 8 can be switched from a poorly resolved multistep redox process to four consecutive well-separated one-electron oxidations, corresponding to the sequential oxidation of the four ferrocenyl moieties.

Thermal ring-opening polymerization of an unsymmetrical silicon-bridged [1]ferrocenophane in coordination nanochannels

Thermal ring-opening polymerization of the unsymmetrically substituted [1]ferrocenophane was performed in one-dimensional nanochannels of porous coordination polymers (PCPs).

Construction of covalent- and hydrogen-bonded assemblies from 1′,1′′′-biferrocenediboronic acid as a new organobimetallic building block

Covalent- and hydrogen-bonded assemblies were constructed from 1′,1′′′-biferrocenediboronic acid as a new organobimetallic building block.