Replacement, of acetylenic hydrogen atom by bromine

Replacement, of acetylenic hydrogen atom by bromine, 46, 86 of acyl chlorine atom by fluoride atom using hydrogen fluoride, 46, 3... 

Replacement, of acetylenic hydrogen atom by bromine, 45, 86 of acyl chlorine atom by fluorine atom using hydrogen fluoride, 46, 3 of amino hydrogen atoms by thio-carbonyl group, 46, 19 of aromatic bromine atom by potassium /-butoxide, 46, 89 of a-chloro atom in ester using azide ion, 46, 47... 

A differentiation between the two subcla.sses Ai and Ao is seldom necessary since this is accomplished in connection with the final identification of the individual compounds. A triple union will usually add four atoms of bromine, but this is true also of the diolcfincs. When both hydrogens of acetylene arc replaced by so-called negative groups (phenyl, carboxyl, etc.) only two atoms of bromine are added. Ethylene derivatives containing such negative groups add bromine rather slowly. (Example Addition of Bf2 to cinnamic acid.)... 

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