Neue Polyiodide des Caesiums mit Doppel‐ und Tripeldecker‐Kationen, [Cs(Benzo‐18‐Krone‐6) 2 ]I x und [Cs 2 (Benzo‐18‐Krone‐6) 3 ](I x ) 2 (x = 3, 5)

New Polyiodides of Cesium containing Double and Triple Decker Cations, [Cs(benzo‐18‐crown‐6) 2 ]I x and [Cs 2 (benzo‐18‐crown‐6) 3 ](I x ) 2 (x = 3, 5) [Cs(b18c6) 2 ]I x (x = 3 (1) , 5 (3) ) and [Cs 2 (b18c6) 3 ](I x ) 2 (x = 3 (2) , 5 (4) ) (b18c6 = benzo‐18‐crown‐6) have been synthesized by the reaction of benzo‐18‐crown‐6 (C 16 H 24 O 6 ), cesium iodide (CsI) and iodine (I 2 ) in acetonitrile ( 1 ), ethanol/dichloromethane ( 2 , 4 ) and 2‐methoxyethanol ( 3 ). Their crystal structures were determined on the basis of single crystal X‐ray data {( 1 ): monoclinic, C2/c, Z = 4, a = 2048.8(5), b = 1329.5(5), c = 1588.7(5) pm, β = 110.23(1)°; ( 2 ): monoclinic, C2/c, Z = 4, a = 2296.0(1), b = 2092.7(1), c = 1373.6(1) pm, β = 100.21(1)°; ( 3 ): monoclinic, P2 1 /n, Z = 4, a = 1586.3(1), b = 1745.5(1), c = 1608.6(1) pm, β = 92.37(1)°; ( 4 ): triclinic, ${\rm P}{\bar 1}$ , Z = 2, a = 1241.7(1), b = 1539.8(2), c = 1938.4(2) pm, α = 91.15(1), β = 100.53(1), γ = 95.26(1)°}. As expected, double decker cations centered by Cs atoms, [Cs(b18c6) 2 ] + , are found in the structures of ( 1 ) and ( 3 ). In contrast, the triple decker cation found in ( 2 ) and ( 4 ) is less common. The triiodide anions of ( 1 ) and ( 2 ) can be regarded as normal and the chain‐type pentaiodide anions of ( 3 ) and ( 4 ) fall into the known systematic sequence of these anions. The differences in the connectivity of the crystallographically independent I 5 − anions in ( 4 ) are surprising with respect to the fact that, so far, independent pentaiodide anions do not show variations in their scheme of connectivity within one crystal structure.