Molecular wire compounds reactions

Heteroaryl groups are present in the 4-pyridyl-ethynyl compounds81,99,100 and their extended variants with C=C-C6H4-C=C-pyr-4 ligands.81,99 These compounds can be quaternized with Mel or coordinated to a metal complex at their terminal pyridyl functions to give species addressed as molecular rods or molecular wires.81,99 Similar reactions were carried out with 3-phenanthrolinyl-ethynyl complexes,62 and special examples are also known with R based on calixarenes.51... 

The reaction of thioxanthone with various 3-thienyllithium compounds is the initial step in the synthesis of the diols such as 602 from which the bis(thioxanthylium) dication 603 is obtained. This species functions as a reversible redox pair with its reduction product, the hexaarylethane, creating an electrochromic system in which electron transfer brings about bond making and bond breaking. These oligomers 604 may be considered to be a new class of molecular wires (Scheme 238) <2004OL2523>. 

The monomers (213), which were ultimately converted into novel conjugated polymers, have been prepared in poor yield by double Wittig reaction of the dialdehyde (212). Bis-Wittig reactions of l,3-propanebis(triphenylphos-phorane) (214) with ferrocenyl aldehydes (215) have been used to prepare a series of bis(ferrocenyl)polyenes (216) containing a central methylene group. These compounds were converted into the corresponding polymethine cations which are prototype molecular wires with redox-active end groups. 

Gp Fe(dppe) is a good end-capping group for long carbon chains, and Lapinte and co-workers have prepared the Gg chain Gp (dppe)FeG8Fe(dppe)Gp by the oxidative coupling reaction of Gp (dppe)Fe(G=GG=GH). The Gs chain compound has been structurally characterized and is shown to act as a molecular wire between the iron centers. 

Fuchs reaction, which was employed for Sonogashira reaction to make compounds 28-31. These compounds were studied as potential redox-active molecular wires. ... 

As an initial exploratory experiment dodecafluoro n-pentane was chosen as a model compound for P.T.F.E. to simulate part of the perfluorinated molecular chain and allowed to adsorb at 0.13 pPa pressure and ambient temperature on a freshly prepared iron film produced by an evaporation process in situ from an iron wire wrapped around a tungsten filament. The events inside the vacuum chamber were followed with an MS 10 mass spectrometer and (where appropriate) a Pi rani gauge. These experiments suggest that the clean iron acts as a catalyst for the breakdown of the perf1uorinated alkane producing a variety of transiently reactive fragments, such as CF2, that in turn may react with the borosilicate (Pyrex) glass walls of the reaction chamber. 

---