Carbonyl oxygen coordinated to potassium in a monomeric and a dimeric crown ether complex: The crystal structure of [18]<O5-(2,2′)benzophenono·24-coronand-5>·KNCS
1983; Elsevier BV; Volume: 74; Linguagem: Inglês
10.1016/s0020-1693(00)81406-1
ISSN1873-3255
Autores Tópico(s)Molecular Sensors and Ion Detection
ResumoColourless crystals of the title compound, Mr = 469.61, are monoclinic, P21/c, a = 21.631(9), b = 9.170(4), c = 23.746(9) Å, β = 93.48(5)°, U = 4701.5 Å3, Dc = 1.327 Mg m−3 for Z = 8. The structure was solved by direct methods and refined to R = 0.058 for 4850 diffractometer data. There are two independent ion pairs per asymmetric unit. In complex A the cation is additionally coordinated to the five ether O atoms (mean distance 2.92 Å) of the macrocycle, to the carbonyl O at 3.049(2) Å and to a symmetry related second >CO at 2.846(2) Å, thus giving rise to a dimer via linkages. The monomeric complex B is characterised by a relatively short >CO··K+ contact of 2.587(2) Å and three strong (mean distance 2.73 Å) and two weak (mean distance 3.14 Å) K+··O(ether) interactions.
Referência(s)