Transition-Metal-Catalyzed Synthesis of 1,3-Diynes and Ynamides from 2-Bromo-1-iodoalkenes
摘要:
Diynes and ynamides are important products in chemical synthesis. An efficient palladium-catalyzed homocoupling reaction of 2-bromo-1-iodoalkenes to give 1,3-diynes has been developed. The reactions are conducted under convenient conditions and provide products in moderate to excellent yields. Moreover, ynamides were synthesized from 2-bromo-1-iodoalkenes and carbamates, and it is noteworthy that this reaction is catalyzed by nanoparticulate copper(I) oxide to give ynamides in high yields.
The reaction of (E)-2-aryl-1-chlorovinyl p-tolyl sulfoxides with lithiumacetylides gave a variety of (Z)-3-arylhex-3-ene-1,5-diynes in yields of up to 80% with high stereoselectivity. The structure of the (Z)-enediyne was confirmed by X-ray molecular structure analysis. The result of the reaction with deuterium- and 13C-labeled sulfoxide suggested that the reaction proceeds through cleavage of the