An unusual oligomerization/oxidation reaction of a 3-boron-substituted 1-phenyl­buta-1,3-diene produces 6,9,16,19-tetra­phenyl-5,15-distyryl-3,13,25,26-tetra­oxa-2,12-dibora­penta­cyclo­[16.2.2.2^8,11.1^2,5.1^12,15]hexa­cosa-1(20),7,10,17-tetra­ene

The unusual title macrocyclic structure, C₆₀H₅₄B₂O₄, has been isolated from exposure of 3-BF₃-1-phenyl­buta-1,3-diene to both air and moisture in an attempt to obtain crystals of the starting butadiene compound. Formation of the macrocycle from six mol­ecules of the starting butadiene material is rationalized and its structural features are compared with those of other B(OR)₂-substituted cyclo­hexane and benzene ring containing structures. Mol­ecules reside on crystallographic centers of inversion and there are no inter­molecular inter­actions of note in the crystal structure.