Butadiyne 1,4-diphenyl

N-Bromoiraides, 46, 88 />-Bromophenyl isothiocyanate, 46, 21 Butadiene, 46, 106 Butadiyne, diphenyl, 46, 39 A -Butenolide, 46, 22 i-Butyl alcohol in synthesis of phenyl 1-butyl ether, 46, 89 1-Butyl azidoacetate, 46, 47 hydrogenation of, 46, 47 1-Butyl chloroacetate, reaction with sodium azide, 45, 47 i-Butyl hypochlorite, reaction with cy-clohexylamine, 46,17 1-Butylthiourea, 46, 72 1-Butylurea, 46, 72... 

The reaction has found limited use for the direct synthesis of terminal polyacetylenes, as illustrated by the formation of phenylhexatriyne (70%) from butadiyne and bromophenylacetylene (equation 12) . The concomitant formation of diphenyl-octatetrayne (30%) in this reaction illustrates the major drawback to this route, i.e. further coupling of the initial product. 

The thermolysis of diphenylzirconocene in the presence of 1,4-diphenyl-1,3-butadiyne gives the seven-membered zirconacyclocumulene 698 via a zirconocene benzyne intermediate, as shown in Scheme 168.523 Coupling reactions... 

Flash-vacuum pyrolysis of 4.5,8-triphenylpyridazino[4,5-z( -l,2,3-triazine (15) led to 1,4-diphenyl-butadiyne (17). 3,6-Diphenyl-4,5-didehydropyridazine (16) was proposed as an intermediate.108 109... 

A ready route to phenylpropynenitrile involves refluxing copper phenylacetylide and cyanogen bromide in ether-acetonitrile. The yield was 60 % but some diphenyl-butadiyne is formed as a by-product. Nitroacetylenes are reactive compounds, and two routes to these compounds have been described starting from trialkyltin acetylides via electrophilic cleavage of the Sn bond-C bond. - ... 

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