2.4- hexadiyne-l,6-diol

With two equivalents of an organomagnesium hahde, a Gtignard reagent is formed, capable of use in further syntheses (35,36). Cuprous salts cataly2e oxidative dimerization of propargyl alcohol to 2,4-hexadiyne-l,6-diol [3031-68-3] (37). 

This is probably an intermediate in the preparation of the 1,6-dichloro compound from 2,4-hexadiyne-l,6-diol and thionyl chloride in DMF. The reaction mixture must be kept at a low temperature to avoid vigorous decomposition and charring. This may be due to interaction with the solvent. 

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. 

Oxidative Coupling or Propargvl Alcohol Preparation of 2,4-Hexadiyn-l,6-diol... 

Toda, F., D. L. Ward., and Hart, H. (1981) Wheel-and-Axile Design as a Source of Host-Guest Compounds. The Crystal Structure of the 2 1 Acetone Tetraphenyl-2,4-hexadiyne-l,6-diol Complex, Tetrahedron Lett., 22, 3865-3868. 

Numerous diacetylene polymerizations have been characterized. To select a few that have been well studied, 2,4-hexadiyne-l,6-diol(bis-(p-toluene sulfonate)) (16), bis-(phenylurethane) (17) [101], and3,5-octadiyne-l,8-diol (18) [104]... 

Chance and Baughman24 studied photoconductivity in poly[2,4-hexadiyn-l, 6-diol bis(p-toluene sulfonate)]25. Simple polyacetylenes such as this one are unique... 

Under the appropriate conditions it undergoes hazardous reactions with Al, tert-butyl azido formate, 2,4-hexadiyn-l,6-diol, isopropyl alcohol, K, Na, sodium azide, hexafluoroisopropylideneamino lithium, lithium. When heated to decomposition or on contact with water or steam it will react to produce toxic and corrosive fumes of CO and Cr. Caution-. Arrangements should be made for monitoring its use. 

Garito, A. F., McGhie, A. R., Kalyanaraman, P. S. Kinetics of solid state polymerization of 2,4-hexadiyne-l,6-diol bis (p-toluene sulfonate). In Molecular metals. Hatfield, W. E. (ed.). New York Plenum Press 1979, pp. 255-260... 

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 . 

PTS-PDA bis(p-toluenesulfonate-2,4-hexadiyne-l,6-diol PVDF poly(vinyl difiuoride)... 

Figure 3.26. Polydiacetylene mesomers (a) and (b) with different energetic conformation. A single crystal of poly(2,4-hexadiyne-l,6-diol-bis-p-toluene-sulfonate) shows strong TP resonances at about 2.7 eV and 2.1 eV, and a weaker TP state that is centered at 1.8 eV when irradiated with a 2 1 ps Ti sapphire laser [405].

Hexadiyne-l,6-diol, 186 Hexaethylbenzene, 826, 828, 1133 Hexaethylphosphorous triamide, 425 Hexafluoro-2-butyne, 425-426... 

In the crystal of l,l,6,6-tetraphenyl-2,4-hexadiyne-l,6-diol and its analogs, solvents or third molecules are included in the vacant holes or channels made by the stacking host molecules [30]. These molecular spaces may include organic free radicals or open-shell organometallics in a specific orientation desirable for the ferromagnetic interaction. This possibility seems to be worthy of further exploration. 

If host and guest molecules mutually recognize their chiralities at inclusion formation, the process could be used for optical resolution. In other words, when the host compound is optically active, one enantiomer of the guest compound should be included selectively. In turn, if an optical active guest molecule forms a crystal inclusion with one enantiomer of the host compound selectively, the host compound yields resolved. This section deals with the resolution via inclusion formation using host compounds such as alkaloids, 2-propyn-l-ols, 2,4-hexadiyne-l,6-diols, 2,2 -dihydroxy-l,r-binaphthol (7), and 2,2 -dihydroxy-9,9 -spirobifluorene (10a). 

R. Zielinski, and J. Kalinowski, The electric permittivity and phase transition in the bis-(toluene sulphonate) of 2,4-hexadiyne-l,6-diol polymer single crystal, J. Phvs. C Solid State Phvs. 20 177 (1987). 

Partial formation. 2,4-Hexadiyne-l,6-diol refluxed 8hrs. with paraformaldehyde and K-carbonate in methanol in the presence of hydroquinone 4- (4-hydroxy-but-2-ynylidene)-l,3"dioxolane. Y 75%. F. e. s. H. Meister, B. 98, 2862 (1965). 

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