Unacfivated alkynes reacted with 1, Cdilithiel , Idiew derivatives in the presenoe of F a affording substituted benzene derivatives via a f o d [ 4 + 21 cydoaddition. Keywords alkenyl iron. alkynes, mmatjc compounds, f o n d [4 + 21 cydoaddition, 1, Cdilithiwl, 3-dienes, organolithium compounds,