Comparison of the bis(ferrocenylethynyl)phenylmethylium cation with bis(ferrocenylethenyl)methylium analogues

Carbocations

“…156 The fragmentation proceeds in polar solvents via a nortricyclyl cation:Z:chloride ion pair where the ions are separated by the spacer Z = CO, CO 2 , or SO 2 . For each of (81), (82), and (83), similar product distributions were observed with the three precursors. This indicates that similar ion pairs are formed.…”

“…The bis(ferrocenylethynyl)phenylmethylium cation (Fc-C≡C-) 2 C + Ph (Fc = ferrocenyl) was prepared. 82 This cation proved to be much less stable than its bis-ethenyl analogue (Fc-CH=CH-) 2 C + Ph.…”

“…155 The exo-isomer of (79) undergoes solvolysis with direct displacement of the leaving group and complete retention of the bicyclic structure. The products obtained on the fragmentation of the oxochlorocarbenes (X = OCCl), chlorocarbonates [X = OC(=O)Cl] and chlorosulfites (X = OSOCl) of (81), (82), and (83) were determined. 156 The fragmentation proceeds in polar solvents via a nortricyclyl cation:Z:chloride ion pair where the ions are separated by the spacer Z = CO, CO 2 , or SO 2 .…”

Synthesis, structures and reactions of some metallocene alcohols

“…We were interested in both [3]metallocenophanes -as potential strained precursors to organometallic polymers [38] -and in (g 5 -cyclopentadienyl)(g 5 -hydropentalene)iron complexes -as precursors to pentalene-bridged bi-and trimetallic species [39]. In principle, ketone precursors to both these types of compounds can be obtained through reaction of metallocenes with acryloyl chloride derivatives.…”

Cyanine‐Like Dyes with Large Bond‐Length Alternation

“…Komatsu et al successfully measured linear absorption and NMR spectra of similar dyes, [8] but such experiments were only possible at low temperature or over time periods of seconds. Arisandy et al reported the synthesis of ferrocenyl cations with two cyclopentadiene units linked by either an alkene or alkyne bridge; [9] although the alkenelinked cations were very stable, the alkyne-linked cations rapidly decomposed to give unidentifiable products. A ruthenium-stabilized ethynyl cation, which was stable under anaerobic conditions, has also been reported.…”