Methyl-3,5-hexadiyn

A similar synthesis starts from commercially available 1,5-hexadiyne and 2-methyl-cyclopent-2-enone. The benzocyclobutene is obtained from a bis-acetylene in a cobalt-catalyzed reaction. It rearranges regio- and stereoselectively to a 3-deoxy steroid derivative. The overall yield from the cyclopentenone was 40% (R.L. Funk, 1977). 

Ethynylallenes [35], the didehydro analogs of vinylallenes, have also been known for some time, the parent system 7 having been obtained in 1960 by reduction of 3-chloro-l,4-pentadiyne (101) with zinc-copper couple in butanol [36] and the 5-methyl derivative 103 by base-catalyzed isomerization of 1,4-hexadiyne (102) with sodium ethoxide in ethanol (Scheme 5.13) [9]. 

Poly(oxycarbonyl-2,4-hexadiyne-1,6-diyl), see Poly(2,4-hexadiyne-1,6-ylene carbonate), 2665 Poly[oxy(methyl)silylene], 0483 Poly(l -pentafluorothio-1,2-butadiyne), 1375... 

When both hydrogens of butadiyne are replaced by methyl groups the reactivity toward nucleophilic addition drops substantially and more drastic conditions are required. Addition of methanol to 2,4-hexadiyne (102, n = 2) requires the use of concentrated alkali at temperatures above 100 °C to give 103 (R = Me) = addition... 

Therefore, 15 is 4-methyl-l,4-octadiene and not 5-methyl-4,7-octadiene. Diynes are similarly named, as in 16, where both CsC units are contained in the longest chain, so it is a hexadiyne. The chain is numbered to give both CsC units the lowest combination of numbers. The position of the CsC units in 16 dictates the position of any substituents on those chains. Diyne 16 is named 3,3-diethyl-l,5-hexadiyne. Cyclic molecules such as 1,3-cycloheptadiene (17) are named using these protocols. In these examples, the primary carbon skeleton and/or ring system is marked in purple, with substituents in green. 

Impedance spectroscopy has been used to study the polymerization of variety of thermoset resins, but only a few investigations have been done on solution polymerization reactions. 5) We will present one of the first impedance measurements that monitors both the surface and bulk photopolymerization of 6-(2-methyl-4-nitroanilino)-2,4-hexadiyn-1 -ol... 

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