1,4-Diphenylbutadiyne reacts with [WI2(CO)3(NCMe)2] in CH2Cl2 to give the iodo-bridged dimer [W(μ-I)I(CO)(NCMe)(η2PhC2C2Ph)]2.1,4-Diphenylbutadiyne on UV irradiation with olefins such as 2,3-dimethyl-2-butene, 1,4-cyclohexadiene and dimethyl fumarate yields cross-cycloaddition products.1,4-Diphenylbutadiyne was used in the preparation of 7,8-dehydropurpurin dimers via two-fold Pd-catalyzed [3+2] annulation of meso-bromoporphyrin. 1,4-Diphenylbutadiyne reacts with [WI2(CO)3(NCMe)2] in CH2Cl2 to give the iodo-bridged dimer [W(μ-I)I(CO)(NCMe)(η2PhC2C2Ph)]2.1,4-Diphenylbutadiyne on UV irradiation with olefins such as 2,3-dimethyl-2-butene, 1,4-cyclohexadiene and dimethyl fumarate yields cross-cycloaddition products. 1,4-Diphenylbutadiyne was used in the preparation of 7,8-dehydropurpurin dimers via two-fold Pd-catalyzed [3+2] annulation of meso-bromoporphyrin.