Using Cu 2+ ‐Centered Complexes as Glue: Two New Layered Polyoxotantalates Based on the Interconnection of the Ta 6 O 19 Moiety

Applying the three different solutions Cu (dien) 2+ in DMSO/H 2 O, acetonitrile, and Ta 6 O 19 6‐ /H 2 O in a layering approach, the two new polyxotantalates Cu (dien) 5 (Cu (dien) (H 2 O) 2) Cu (Ta 6 O 19) 2 ·DMSO·32 H 2 O (I) and K 2 (Cu (dien) ) 6 Cu (Ta 6 O 19) 2 ·26H 2 O (II) (dien = diethylenetriamine) could be synthesized at room temperature within a short time. In the structures of I and II, a Cu 2+ cation and two Cu (dien) 2+ complexes connect two T 6 O 19 clusters, forming a (Cu (dien) ) 2 Cu (Ta 6 O 19) 2 unit. In the structure of I, two such units are present, which are crystallographically independent but structurally nearly identical. One of the (Cu (dien) ) 2 Cu (Ta 6 O 19) 2 units is expanded by six Cu 2+ ‐centered complexes, while the second group has TaOCuOTa bridges to eight complexes and forms nearly straight chains. These chains are connected by the former (Cu (dien) ) 2 Cu (Ta 6 O 19) 2 moiety, thus generating layers that contain pores. In the structure of II, the (Cu (dien) ) 2 Cu (Ta 6 O 19) 2 unit is structurally very similar to those of I. The building block is expanded by eight Cu 2+ ‐centered complexes, of which two are terminally coordinated. Each (Cu (dien) ) 2 Cu (Ta 6 O 19) 2 unit is connected to four other units via TaOCuOTa bonds to form a puckered layered structure containing pores. The K + ion is coordinated by nine O atoms in a strongly distorted tricapped trigonal prism.