Structures of 1,1 ',3,3 '-tetra(2-methyl-2-nonyl)ferrocenium(1+) salts of CB11H12-, B12F122-, BF4-, PF6-, and ClO3-

The interdigitated and layered structures of the tetraalkylferrocenium salts [DEC][CB11H12], [DEC](2)[B12F12], [DEC][BF4], [DEC][PF6], and [DEC][ClO3] were determined by single-crystal X-ray diffraction (DEC+ = 1,1 ',3,3 '-tetrakis(2-methyl-2-nonyl)ferrocenium(1+)). The structures of the salts of the two smaller anions were similar to the previously published oxoanion structures of [DEC][XOn-](XOn- = NO3-, ClO4-, and ReO4-), with layers of trigonal-pyramidal ClO3- or tetrahedral BF4- anions stuffed between layers of interdigitated ferrocenium ions. The DEC+ cations in structures with the more highly charged and/or larger anions B12F122-, CB11H12-, and PF6- are also layered but the interdigitation is not as regular and not as complete as in the structures with relatively small 1- anions. Other differences and similarities of the eight [DEC](n)[X] structures (n = 1, 2) are discussed. (C) 2018 Elsevier B.V. All rights reserved.