Diacetylenic compound

It is known that diacetylenes (in Favorsky s reaction, for example) are 1000-fold more active than monoacetylenes. It is of interest to consider how the accumulation of triple bonds will affect the compound acidity. However, in the literature there are no data on the CH acidity of diacetylenic compounds. We were the first to estimate the p/ifa of a monosubstituted diacetylene, 4-butadiynyl-l,3,5-trimethylpyrazole, to be about 24-26 log units. Unfortunately, the authors (83IZV466) have failed to determine the acidity of the diyne more accurately owing to the side processes of remetallization that complicate control over reaction. 

One of these reactions, namely the oxidation of the cuprous complexes of 2-thienyl and 2- and 3-substituted thienylacetylenes, was studied in this laboratory (80). It has been found that this reaction proceeds in an analogous manner to that in other aromatic series. The yields of the corresponding diacetylenic compounds were high and depended on the oxidizing agent applied. The cuprous complexes of 2-thienylacetylene and 2- and 3-substituted thienylacetylenes are bright yellow substances, stable at room temperature. They could be readily utilized for the determination of thienylacetylenes as well as for cuprous ions. 

The polymerization proceeds under photo- [49,50],X-ray [51], and y-ray [52] irradiation in the dark in vacuo, in air, or even in water or organic solvent as the dispersant (nonsolvent) for the crystals, similar to the solid-state polymerization of diacetylene compounds [ 12]. The process of topochemical polymerization of 1,3-diene monomers is also independent of the environment surrounding the crystals. Recently, the thermally induced topochemical polymerization of several monomers with a high decomposition and melting point was confirmed [53]. The polymer yield increases as the reaction temperature increases during the thermal polymerization. IR and NMR spectroscopies certified that the polymers obtained from the thermally induced polymerization in the dark have a stereoregular repeating structure identical to those of the photopolymers produced by UV or y-ray irradiation. 

The present polymerization principle (the 5 A rule) for the 1,3-diene monomers seems to have features similar to the empirical rules for the polymerization of diacetylene compounds reported in the literature dg 5 A and 0-45°... 

Monosubstituted acetylenic compounds can be oxidatively dimerized by air at room temperature in the presence of copper salts in a pyridine-methanol solution. This method has been applied to a wide variety of acetylenic compounds and gives high yields in disubstituted diacetylenic compounds (equation 264).590... 

Keywords acetylenic compound, CuCl2, Glaser coupling, diacetylenic compound... 

We can mention diols but also less abundant ones such as diepoxies [1], diamines [2, 3], diisocyanates [4, 5], dialdehydes [6] and diacetylenic compounds [7]. 

In addition, the Japanese Companies, the Hitachi Chemical Co and the Mitsui Toatsu Chemical Inc. have developed interesting applications with polyimides semi-conductors, liquid crystals, poorly colorable thermostable films [103-107], Finally, let us mention monomers obtained from diamines first the synthesis of a diacetylenic compound [7] ... 

Polymer industries depend on the spontaneous polymerization of molecules into chains in response to an appropriate trigger. Polymerization reaction under STM was first observed by Grim et al., although the reaction itself was not induced with a current from the tunneling probe [37]. Recently, by using an STM tip, Okawa and Aono have successfully initiated and terminated the linear propagation of the chain polymerization of a diacetylene compound into a polydiacetylene compound at any chosen point with a spatial precision of about 1 nm [38]. 

Klebanskii, A. L., Grachev, I. V., Kuznetsova, O. M. Reaction of formation of diacetylenic compounds, from monosubstituted derivatives of acetylene. I. Mechanism of formation of diacetylenic compounds. Zh. Obshch. Khim. 1957, 27, 2977-2983. 

The foregoing synthesis has been considerably simplified by the discovery that 2 6-distyrylpyridine rapidly adds two moles of bromine and the resulting compound on treatment with alcoholic potash gives rise to 2 6-diphenethinylpyridine (LXIV). Hydration of this diacetylenic compound with sulfuric acid yields 2 6-diphenacylpyridine (LXV) which can be hydrogenated in methanol over a platinic oxide-barium sulfate catalyst... 

Diacetylene compounds with two nonconjugated acetylene groups, especially ol,oj-diynes may undergo various types of polymerization to provide polymers with different main chain structures. 

The addition of diphenyltin dihydride to diacetylenic compounds is also reported to give polymers. 

In 1960 Hay [30] reported that various diacetylenic compounds undergo oxidative coupling with the aid of copper(I) chloride-amine complexes and oxygen to give polymeric products. 

From acetylenic compounds, central or terminal, dichlorocyclobutenones are formed.247 Diacetylenic compounds provide the monoadducts in the two cases tested. a-Unsaturated cyclic ethers (dihydrofuran and -pyran) xmdergo a clean reaction.248 With 1,4-dioxene, a convenient access to semisquaric acid is obtained, even if the yield of the first step is modest.249... 

Route I Diacetylenic compound = Run X-Ar-X A Catalyst Time (h) Yield (%) Polymer obtained... 

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