Dibenzopentalenes from B(C₆F₅)₃‐Induced Cyclization Reactions of 1,2‐Bis(phenylethynyl)benzenes

'Lene' and mean: The strong Lewis acid B(C6F5)3 efficiently converts some bis(arylethynyl)benzenes into dibenzopentalenes through a series of Lewis acid induced cyclization reactions at room temperature. Thus the reaction has the potential to be useful in the synthesis of substituted dibenzopentalene derivatives which are difficult to make by conventional means.