Diacetylenes, substituted

It should be noted that functionalised diacetylene monomers have also been used for coupling reactions with haloarenes. By reacting diacetylene-substituted p-aminoanilines [135] and diethynyl(methyl)( -octyl)silane [136] with diiodoarenes, polyamides and polysilanes have been prepared, respectively. 

Nos. 1-3, 1st April 1995, p. 1825-6 FTIR AND NIR-FT-RAMAN STUDY OF POTENTIAL MOLECULAR FERROMAGNETICS - POLY(DIACETYLENES) SUBSTITUTED WITH NITROXYL RADICALS Shchegolikhin A N Lazareva O L Ovchinnikov A A Spector V N... 

Chemical properties of deposited monolayers have been studied in various ways. The degree of ionization of a substituted coumarin film deposited on quartz was determined as a function of the pH of a solution in contact with the film, from which comparison with Gouy-Chapman theory (see Section V-2) could be made [151]. Several studies have been made of the UV-induced polymerization of monolayers (as well as of multilayers) of diacetylene amphiphiles (see Refs. 168, 169). Excitation energy transfer has been observed in a mixed monolayer of donor and acceptor molecules in stearic acid [170]. Electrical properties have been of interest, particularly the possibility that a suitably asymmetric film might be a unidirectional conductor, that is, a rectifier (see Refs. 171, 172). Optical properties of interest include the ability to make planar optical waveguides of thick LB films [173, 174]. 

According to publications (68LA113 71CAS1731 72BSF4781), disubstituted diacetylenes react with diazomethane to form both 3- and 4-acetylenyl-substituted... 

If the reaction of diacetylene and its substituted derivatives with ammonia or primary amines is carried out in the presence of a copper(I) salt, the main reaction product formed in an autoclave after brief heating to 150°C turns out to be pyrrole or pyrrole derivatives 1 (65CB98 71MI1). 

Carbanions of substituted diacetylenes 68 generated under the action of complex superbase -BuLi/t-BuOK/THF/hexane add to carbon disulfide to afford the intermediates 69 which further transform to thieno[2,3-i]thiophenes (70) (90DIS 91SC145). 

Acetylene- and Diacetylene-Expanded Cycloalkanes and Rotanes. 201 1 -42 de Meijere A, Kozhushkov SI, Khlebnikov AF (2000) Bicyclopropylidene - A Unique Tetra-substituted Alkene and a Versatile Cj-Building Block. 207 89-147 de Meijere A, Kozhushkov SI, Hadjiaraoglou LP (2000) Alkyl 2-Chloro-2-cyclopropylidene-acetates - Remarkably Versatile Building Blocks for Organic Synthesis. 207 149-227 Dennig J (2003) Gene Transfer in Eukaryotic Cells Using Activated Dendrimers. 228 227-236 de Raadt A, Fechter MH (2001) Miscellaneous. 215 327-345 Desreux JF, see Jacques V (2002) 221 123-164... 

Polydiacetylenes which constitute an important class of polenynic polymers can be synthetized photochemically in the solid state from substituted diacetylenes. Experimental... 

Kamada K, Ohta K, Iwase Y, Kondo K (2003) Two-photon absorption properties of symmetric substituted diacetylene drastic enhancement of the cross section near the one-photon absorption peak. Chem Phys Lett 372 386-393... 

Ohta K, Kamada K (2006) Theoretical investigation of two-photon absorption allowed excited states in symmetrically substituted diacetylenes by ab initio molecular-orbital method. J Chem Phys 124 124303... 

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>. 

The two-step process of epitaxial polymerization has been applied to symmetrically substituted diacetylenes First, the monomers have been crystallized epitaxially on alkali halides substrates from solution and the vapor phase. The oriented monomer crystals are then polymerized under the substrate s influence by gamma-irradiation. The diacetylenes in this study are 2,4-hexadiyn-l,6-diol (HD) and the bis-phenylurethane of 5,7-dodecadiyn-l,12-diol (TCDU). The polydiacetylene crystal structures and morphologies have been examined with the electron microscope. Reactivity and polymorphism are found to be controlled by the substrate. 

The urethane-substituted polydiacetylenes exhibit thermo-chromic transition with low and high temperature crystal phases favoring acetylenic and butatriene backbone, respectively (4-6). Our interest in the application of epitaxial polymerization to diacetylenes has been the possibility of substrate control over orientation, structure, and the single crystal nature of thin films. 

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. 

Organyl tellurolate anions effect 1,4-additions to acetylenes bearing electron-withdrawing groups such as acetylenic ketones, aldehydes, esters, diacetylenic ketones, " as well as acetylenic phosphonates and sulphones giving 2-substituted vinyl tellurides with Z configuration. 

In some derivarization reactions with mono-metallaied bmadiyne, considerable amounts of disubstimted diacetylene are farmed. Their presence can hamper the purification of the desired mono-substitution products, particularly when the boiling point is high and the thermal stability limited. The formation of disubstitution products can be effectively suppressed, however, by using a large excess of butadiyne. The preparation of butadiynvl tributyltin is an illustrative example. 

The extensive studies of the behavior of mixed monolayers or bilayers of di-acetylenic lipids and other amphiphiles parallel to some degree the studies of dienoyl-substituted amphiphiles. Since the dienoyl lipids do not contain a rigid diacetylenic group in the middle of the hydrophobic chains, they tend to be miscible with other lipids over a wide range of temperatures and compositions. In order to decrease the lipid miscibility of certain dienoyl amphiphiles, Ringsdorf and coworkers utilized the well-known insolubility of hydrocarbons and fluorocarbons. Thus two amphiphiles were prepared, one with hydrocarbon chains and the other with fluorocarbon chains, in order to reduce their ability to mix with one another in the bilayer. Of course it is necessary to demonstrate that the lipids form a mixed lipid bilayer rather than independent structures. Elbert et al. used freeze fracture electron microscopy to demonstrate that a molar mixture of 95% DM PC and 5% of a fluorinated amphiphile formed phase-separated mixed bilayers [39]. Electron micrographs showed extensive regions of the ripple phase (Pb phase) of the DM PC and occasional smooth patches that were attributed to the fluorinated lipid. In some instances it is possible to... 

This procedure has been shown3 to be extremely general and applicable to a wide variety of straight-chain 1-acetylenes, 4-substituted 1-acctylenes, and a,co-diacetylenes, together with primary halides, sterically hindered primary halides, secondary halides, and a,a>-dihalides. 

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