Ferrocenyl D–π–A conjugated polyenes with 3-dicyanomethylidene-1-indanone and 1,3-bis(dicyanomethylidene)indane acceptor groups: Synthesis, linear and second-order nonlinear optical properties and electrochemistry

Dipolar Second-Order Nonlinear Optical Chromophores Containing Ferrocene, Octamethylferrocene, and Ruthenocene Donors and Strong π-Acceptors: Crystal Structures and Comparison of π-Donor Strengths

“…Both crystallographic and computational geometries indicate little contribution from the [(η 6 -fulvene)CpM] + resonance form in 1–6 , consistent with the crystal structure of III ,11 but in contrast to that of I ,9 in which the bridging CH group is clearly bent towards the metal atom. The similarity in π-donor strengths of Fc and Rc found in the present compounds is at variance with previous cationic examples where the [(η 6 -fulvene)CpM] + structure type dominates and where Rc is a much stronger π donor,6,8 presumably due to the role played by the more diffuse 4d orbitals of ruthenium in facilitating coordination to the bridging carbon atom 73.…”

“…The average BLA parameters for 1–6 and the closely analogous III 11 indicate significant contribution from zwitteronic resonance forms in metallocenyl chromophores of this type with very strong non-aromatic π-acceptors. In polyenes without significant donor/acceptor π-interaction,41–46 including ferrocenyl-terminated examples,47 typical bond-length alternations are 0.10–0.12 Å.…”

Oligomerization of phenylferrocenylacetylene under the action of WCl6

“…The polymerization of diphenylacetylenes containing the ferrocenyl group in para-or meta-positions was accomplished in the presence of catalytic system TaCl 5 -nBu 4 Sn [10]. Recently [11], dipolar second-order nonlinear optical chromophores containing ferrocene donor entity and 3-dicyanomethylidene-1-indanone acceptor group bridged by the polyene chain of different length were synthesized.…”

“…Polymerization of such acetylenes is known to be substantially hampered due to steric hindrances toward the growth of polymer chain imposed by the phenyl substituents. It is not occasionally that the polymers of internal acetylenes with ferrocene substituents are virtually unknown, the only exception being likely the above-cited work [11]. Meanwhile, the introduction of extra benzene substituent into every unit of the polyene increases conjugation degree and ability of the polyconjugated chain to electron transfer.…”

Pyridinium Conjugated Ferrocenes with Thien and Bithien Bridges: Synthesis and Electrochemical Properties

“…[1][2][3][4][5] Since the ferrocene moiety can be switched from a good donor in the reduced state to a weak attractor in the oxidized one, the compounds, with ferrocenes linked to a pyridinium, also provide molecular switch for many physical properties. [6][7][8] We have reported a series of pyridinium conjugated ferrocenes and their electrochemical properties.…”