Triaxially Woven Hydrogen-Bonded Chicken Wires of a Tetrakis(carboxybiphenyl)ethene.

Abstract

Interpenetration of low-dimensional networked structural motifs crucially affects porosity, stability, and properties of the whole reticular framework. However, varying and controlling the manner of interpenetration is still challenging. Herein, a porous hydrogen-bonded organic framework (HOF) with wvm-like weave constructed by triaxially woven chicken wires of X-shaped tetra-armed tetrakis(carboxybiphenyl)ethene CBPE, formally 4',4''',4''''',4'''''''-(ethene-1,1,2,2-tetrayl)tetrakis(1,1'-biphenyl-4-carboxylic acid), is reported. The structure is a contrast to a non-interpenetrated layered framework composed of tetrakis(4-carboxyphenyl)ethene CPE. This exotic framework of CBPE is due to the disproportionate conformation of the outer four phenylene rings in the peripheral biphenyl arms. The activated framework CBPE-1a exhibits thermal stability up to 220 °C and a BET surface area of 555 m2 g-1 . Additionally, the HOF shows mechanochromic behavior in terms of fluorescence color and quantum efficiency. The achievement of the present HOFs can provide insight into constructing a new type of functional porous organic materials with interwoven network structures.