Inclusion property and Diels-Alder reaction of bis(diphenylphosphine oxide)butadiyne

The host molecule, his (diphenylphosphine oxide) butadiyne (2), includes a variety of guests to form five complexes (2a-2e). In addition, the Diels-Alder reaction between 2 and anthracene gives 9, 9', 10, 10'-tetrahedron-9, 9', 10, 10'-biethenoantracene-11, 11'-bis (diphenylphosphine oxide) (3) which is a potential di-pi-methane reactant and can undergo photorearrangement.