Two Three-Dimensional Metal−Organic Frameworks from Secondary Building Units of Zn8(OH)4(O2C−)12 and Zn2((OH)(O2C−)3: [Zn2(OH)(btc)]2(4,4‘-bipy) and Zn2(OH)(btc)(pipe)

Two three-dimensional metal−organic frameworks, [Zn 2 (OH)(btc)] 2 (4,4‘-bipy) and Zn 2 (OH)(btc)(pipe) (btc = 1,3,5-benzenetricarboxylate; 4,4‘-bipy = 4,4‘-bipyridine; pipe = piperazine) with respectively the largest pure zinc clusters of Zn 8 (OH) 4 (O 2 C−) 12 and interpenetrating networks, were synthesized by hydrothermal reactions and characterized by single-crystal X-ray diffraction.