As part of a systematic Study on the synthesis and binding properties of a series of cyclophane ester hosts, the crystal structures of the cyclodimeric propylene-1,3-phenylenediacetate (C26H28O8) and of its di-n-butyltin dichloride complex {(C26H26O8) [SnCl2(C4H9)2]2} have been determined by X-ray analyses. The crystals of the free macrocycle are triclinic, space group P1̅, with a = 5.071(6), b = 8.108(3), c = 14.640(4) Å, α = 76.46(3), β = 85.35(8), γ= 86.04(7)°, Z = 1. Similarly, the crystals of the complex belong to the P1̅ space group of the triclinic system and have the following cell parameters: a = 8.378(4), b = 11.524(3), c = 14.009(4) Å, α = 109.16(2), β = 92.64(2), γ= 100.93(3)°, Z= 1. The most important feature of the complex structure is represented by the unambiguous interaction between two cyclophane ester carbonyls and two molecules of Bu2SnCl2, the distance being 2.865(4) Å. The usual tetrahedral geometry of the organotin(IV) center is significantly influenced by the interaction, changing into a distorted trigonal bipyramid, with a longer apical distance, typical of the five-coordinate stannate complexes. Conformations of the cyclophane in the two structures have been analyzed in some detail.