Eglington reaction

Some of the most useful synthetic transformations of terminal alkynes involve intermolecular and intramolecular homo- and cross-coupling reactions between their. sp-carbon centers, leading to butadiyne or polyyne derivatives. The two most widely used and practical systems are (i) oxidative homocoupling reactions, i.e. Glaser and Eglington reactions and (ii) heterocoupling reactions, i.e. Chodkiewicz-Cadiot coupling of a terminal alkyne with a haloalkyne. 

Recently oxidative coupling reactions of a,a>-diethynyl compounds have been applied in the synthesis of cyclophanes, which are interesting functional host molecules. Whitlock and coworkers, - for example, have reported the synthesis of the water-soluble cyclophane (21), designed as an esterase mimic by the Eglington reaction of (20 Scheme 8). 

Toda and coworkers have found drastic differences in the reaction behavior of racemic and optically active 3,6-di-r-butylocta-l,4,7-triyne-3,6-diol (17) upon oxidative coupling by the Eglington method.- - Thus, the noncentrosymmetric cyclic dimers, (18a) and (18b), can be obtained from the racemic monomer, but the corresponding optically active monomer does not lead to any of the cyclic dimer. In the latter case the optically active polymer (19) is obtained as the sole isolable product (Scheme 7). 

Organic reactions in the solid state, e. g. Baeyer-Villiger, Reformatsky, Luche, Glaser, Eglington, Wittig, Brown. Michael, Robinson often more efficient than in solution. 

Similar techniques have been tested by various authors297 for a variety of substituted and also for long-chain acetylenes. The reaction is particularly smooth in the presence of a copper(i)-amine complex in an organic solvent pyridine and A A A -tetramethylethylenediamine have been used as the amine.298 Detailed directions for the preparation of 1,4-diphenylbutadiyne by oxidative dimerization of phenylacetylene have been given by Campbell and Eglington.299... 

EDA complex formation, phase transitions 339 edge dislocation, Volterra process 419 effusity, phase transitions 320 Eglington-Glaser reaction, synthesis 99 eigenwaves, SLM 764 Einstein diffusivity-viscosity law 585... 

Corbett, D. F., A. J. Eglington, and T. T. Howarth Structure Elucidation of MM 17880, a New Fused p-Lactam Antibiotic isolated from Streptomyces olivaceus a Mild p-Lactam Degradation Reaction. J. C. S. Chem. Commun. 1977, 953. Butterworth, D., M. Cole, G. Hanscomb, and G. N. Rolinson Olivanic Acids, A Family of p-Lactam Antibiotics with p-Lactamase Inhibitory Properties Produced by Streptomyces species. I. Detection, Properties and Fermentation Studies. J. Antibiotics 32, 287 (1979). 

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