Rhodium(I)‐Catalyzed Ring‐Closing Reaction of Allene–Alkene–Alkynes: One‐Step Construction of Tricyclo[6.4.0.0^2,6] and Bicyclo[6.3.0] Skeletons from Linear Carbon Chains

Abstract

Treatment of dodecatrienyne derivatives with [RhCl(CO)₂ ]₂ in refluxing toluene effected the cycloisomerization to produce tricyclo[6.4.0.0^2,6 ]dodecadienes. The one-carbon shortened undecatrienyne derivatives, however, afforded bicyclo[6.3.0]undecatriene derivatives instead of tricyclic compounds, the latter of which are well known as a basic skeleton of naturally occurring octanoids. On the basis of two experiments with deuterated substrates, a plausible reaction mechanism for the construction of these products was proposed.