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A barium perchlorate complex with a lateral macrobicycle derived from 4,13-diaza-18-crown-6 containing a pyridine
Fernando Avecilla1, David Esteban, Carlos Platas-Iglesias
1Departamento de Química Fundamental, Universidade da Coruña, Campus da Zapateira s/n, E-15071 A Coruña, Spain.
Abstract:
In the crystal structure of (perchlorato-kappa(2)O,O'))(28,31,36,39tetraoxa-1,9,17,25,42-pentaazapentacyclo[23.8.5.1(11,15).0(3,8).0(18,23)]nonatriaconta-3,5,7,9,11,13,15,16,18,20,22-undecaene-kappa(8)N(1),N(9), N(17),N(42),O(28),O(31),O(36),O(39))barium(II) perchlorate, [Ba(ClO(4))(C(33)H(41)N(5)O(4))](ClO(4)), the Ba(II) cation is situated in the macrobicyclic cavity, bound to only eight of the nine available donor atoms of the Schiff base macrobicyclic receptor. The pivotal N5 atom does not belong to the coordination sphere of the Ba(II) ion, in spite of its endo conformation with the lone pair directed towards the inside of the cavity. The Ba(II) ion completes its coordination core with two O atoms of one bidentate perchlorate group.
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