Diacetylene derivatives

LB films of CO-tricosenoic acid, CH2=CH—(CH2)2qCOOH, have been studied as electron photoresists (26—28). A resolution better than 50 nm could be achieved. Diacetylenic fatty acids have been polymerized to yield the corresponding poly (diacetylene) derivatives that have interesting third-order nonlinear optical properties (29). 

Thus, the reaction of diazoalkanes andnitrilimines with diacetylenic derivatives can be used as a method for synthesizing acetylenylpyrazoles. 

Because diacetylene is unstable, a stable diacetylene derivative, 1-methoxybut-l-en-3-yne (65CB98), is often employed in the synthesis of pyrroles. The reaction with ammonia proceeds under conditions of heterogeneous catalysis (a mixture of reagent vapors is passed through a catalyst-containing reactor heated to 150°C), approaching a yield of 50-70% but with primary aromatic amines, the yield drops to 20%. 

As mentioned in the introduction, l-heterobut-l-en-3-ynes, RXCH=CHC=CH (X = RN, O, S R = organic radical), are the nearest and most important diacetylene derivatives readily formed by nucleophilic addition of amines, alcohols, and thiols to diacetylene. In many heterocyclization reactions (especially those leading to fundamental heterocycles) l-heterobut-l-en-3-ynes behave as diacetylene synthetic equivalents, but unlike diacetylene, they are nonhazardous. Therefore, the syntheses of heterocycles therefrom are often more attractive in preparative aspect. 

This section deals with the reactions of 4-dialkylaminobut-3-yn-2-ones representing diacetylene derivatives (69HCA2641 87ZOR1635 91UK103 92KGS867 00UK642). 

Tieke, B. Polymerization of Butadiene and Butadiyne (Diacetylene) Derivatives in Layer Structures. Vol. 71, pp. 79 — 152. 

Organoboration of diacetylenic derivatives proceeds stepwise and in a number of cases is also accompanied by 1,2-anionotropic rearrangement giving rise to polycyclic compounds (see Section 12.13.4.2) <2001CEJ775, 2002CEJ1537>. 

Nucleophilic substitution of the nitro group in 3-amino 4-nitrofurazan 185 under conditions of phase-transfer catalysis gave a series of acetylene and diacetylene derivatives (Scheme 43) <2001RJ01629>. 

Another example of solid-state polymerisation is polymerisation of diacetylene derivatives which results in the formation of highly crystalline polymer that also conducts electricity. 

The second reaction we will treat here that in many cases proceeds by a homogeneous mechanism is the solid-state polymerization of diacetylenes. The photolability of these compounds has long been known (189), but it was not until the appearance of the pioneering works of Hirshfeld and Schmidt (168) and of Wegner (190) that some real understanding of the process was introduced. This led to an explosive interest in the subject, and more than 200 diacetylene derivatives have now been studied, by a wide variety of techniques (191). 

In the authors laboratory the ultraviolet absorption spectra of azlactones (76) as well as of diacetylenic derivatives were investigated... 

Mannich condensation of o-hydroxyphenylacetylene (227, R = H) leads to compound 228 heterocyclic ring closure of the latter gives the basic 2-substituted benzofuran 229. The diacetylenic derivative (227, R = C=CH) gives the corresponding 5-ethynylbenzofuran (229, R = C=CH).488... 

A general method of synthesis of l-hetera-4-telluracyclohexa-2,5-dienes 90 is founded in the nucleophilic addition of telluride anion to type 91 diacetylene derivatives. The telluride dianion is prepared in situ from the elements in liquid ammonia. The reaction was carried out with methanol or mixtures with DMSO and liquid ammonia as solvents, with the following diacetylenes di(l-alkynyl)sulfides (73RTC1326), I-alkynylethynyl sulfides (75RTCI63), di(l-alkynyl)sulfones (78RTC244), and di(l-alkynyl)phosphi-noxides (75RTC92). 

An example of the possiblities in this respect is the polymerization of acetylene and diacetylene derivatives, i. e. of multifunctional monomers, with several degrees of freedom in the addition to the active centre. Generally a poorly defined mixture of mostly insoluble products is formed. On the other hand, polymerization of many substituted diacetylenes in the solid phase is easy. By short-wave irradiation (UV, j>) or simple tempering below the melting... 

One of the current areas of intense activity is the solid-state polymerization of certain diacetylene derivatives, a reaction in which conjugated polyenepolyyne chains are created with effectively infinite length (see Section IV.F). 

Certain diacetylene derivatives undergo a remarkable polymerization reaction in the solid state under the influence of heat, ultraviolet light. X-rays or y radiation - . The reaction involves 1,4-addition of the conjugated triple bonds and produces a... 

A single crystal of monomer becomes a nearly defect-free single crystal of the polymer . The two most commonly used monomers are the phenylurethane and tosylate derivatives of 2,4-hexadiyne-l,6-diol, 233a and 233b, but the reaction has been accomplished with a variety of symmetrical and unsymmetrical diacetylene derivatives . 

Tieke, B. (1985) Polymerization of butadiene and butadiyne (diacetylene) derivatives in layer structures. Adv. Polym. Sci., 71, 79-151. 

In recent years interest in these materials has grown mainly for physical reasons. The layer perovskites are looked at as model compounds for the study of magnetic properties in two-dimensional systems (J2) and as models for the study of structural phase transitions in lipid bilayer-type arrays ( ). The use of layer perovskites as a matrix for organic solid state reactions represents a fairly new research topic. First experiments were carried out studying the photolysis of butadiyne (diacetylene) derivatives (li-ZSl) For a corresponding study of the butadiene derivatives the compounds listed in Table I were synthesized. 

Figure 2.3.11 Ball-and-sticl< representations of the crystal structures of co-crystals of diacetylene derivatives involving (a) a dicarboxylic acid host (b) a bis(pyridine) host.

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