Polyynes polymers

FIGURE 3. Chemical structures of platinum(II) polyyne polymers 1—75. 

A new family of Pt(II) polyyne polymers functionalized with substituted 1,4-diethynylbenzene derivatives 8—14 were synthesized and optically characterized by absorption and PL studies.20 In regard to the emission properties, it is interesting to see that the relative intensity of triplet emission increases strongly with the electronegative fluorine content in such system. 

A new Pt(II) polyyne polymer, P15, prepared from the reaction of cfs-[Pt(PPh3)2Cl2] with l,4-diethynyl-2,5-dihexadecyloxybenzene using the extended one pot polymerization route, was tested for its sensing properties and showed fast and reproducible response to relative humidity variations and methanol vapor in surface acoustic-wave (SAW) sensors.46 A SAW sensor was fabricated from polymer P15 as a sensitive membrane, and the polymer was deposited as thin film on the surface of SAW delay lines implemented on three different piezoelectric substrates. High sensitivity and reproducibility were recorded for such devices. The acoustic characterization of the polymer film was also studied with the aid of theoretical results obtained by the perturbation theory. 

The synthesis of several high molecular-weight platinum polyyne polymers carrying chiral (R)-l,l -bi-2-naphthol bridge, P17, was described.48 These represent the first examples of metal acetylide polymer with an optically active backbone. They display much larger specific negative optical rotations than both the metal-free alkyne precursors and their corresponding dinuclear model compounds. These results support the fact that the main chain of P17 adopts a one-handed helical conformation and induces the helical chirality of the polymers. 

An interesting class of cationic polyyne polymers 187 was prepared by reaction of the bimetallic complex, p-butadiynediyl-bis[/ra//i--chlorobis(tri-//-butylphosphine)palladium], with an equimolar amount of 4,4 -bipyridyl in... 

Group 10 metal polyyne polymers of type 165 and 166 generally show good stability in air in the solid state. ... 

Table 3 Thermal stability of group 10 metal polyyne polymers (measured by TGA at heating rate of 5 °C min )...

A step-growth polycondensation route has been succesfully devised to prepare novel nickel polymers 207 with arene spacer groups. The procedure involved the polycondensation of the fluorinated dilithiated species 206 and an Ni(ii) complex (Equation (75))." " The rod-like structure of these polymers was established by dilute-solution viscosity measurements, and the results were similar to those reported for the related platinum polyyne polymers 166 (M = Pt(P Bu3)2 x = 2) (Section 12.06.5.2.3). 

The absolute moleeular weights of these materials have been established by GPG by means of the universal calibration technique that involves the acquisition of intrinsic viscosity data. As with the aforementioned platinum polyyne polymers 166 (M = Pt(P"Bu3)2 x = Z), the intrinsic viscosities were found to be independent of the nature of the solvent and a Mark-Houwink a-value of 1.5 was determined, which is indicative of a rodlike structure. Interestingly, it was found that in this case, GPG, using PS standards, underestimates the true molecular weight of the polymers. This was attributed to the high molar mass of a repeat unit in the Ni polymer 207 compared to PS, which overcompensates for the effect of the rigid-rod structure that would be expected to lead to the opposite situation. Absolute values of of up to ca. 1 x 10 were determined for the polymer samples. 

Alkynyl ligand transfer from Cu to group 10 metals is applied to synthesis of metal containing polyyne polymers. An equimolar reaction of bis(ethynyl)pal-ladium complex and dihalogenopalladium complex in the presence of base and Cul causes condensation to give the polymer having ethyndiyl and Pd in an... 

An interesting class of cationic polyyne polymers (5.24) was prepared by reaction of the bimetallic complex /i-butadiynyl-bis[transmain chain (Eq. 5.13). Other analogous polyelectrolytes have been obtained similarly by the use of the appropriate dihalide complex and bipyridyl derivatives [37]. 

Figure 3.2 General skeleton of transition metal polyyne polymers...

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