The title compound, C42H34O2, crystallizes in the space group R (3) over bar with one molecule disordered at a crystallographic (3) over bar site and another in a general position, The conformation of the linkage of the trityl groups to the central butyne group is such that the O-C ... C-O grouping forms a torsion angle of magnitude 87.2(2)degrees. The C=C length in the ordered molecule is 1.176(3) Angstrom.