Original scientific paper

Crystal and Molecular Structure of the Cyclodimeric Propylene-1,3-phenylenediacetate and of Its Di-n-butyltin Dichloride Complex

Paolo Dapporto ; Dipartimento di Energetica »Sergio Stecco«, Università di Firenze, I-50139 Firenze, Italy
Stefano Roelens ; CNR, Centro di Studio sulla Chimica e la Struttura dei Composti Eterociclici e loro Applicazioni, Dipartimento di Chimica Organica, Università di Firenze, I-50121 Firenze, Italy
Patrizia Rossi ; Dipartimento di Energetica »Sergio Stecco«, Università di Firenze, I-50139 Firenze, Italy

Abstract

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.

Keywords

tin complex; X-ray structure; cyclophane derivatives

Hrčak ID:

132175

URI

https://hrcak.srce.hr/132175

Publication date:

1.9.1999.

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