Isoreticular synthesis of 2D MOFs with rotating aryl rings

A series of isoreticular two-dimensional metal-organic frameworks (MOFs) was synthesized with group 11 metals and semirigid ligands that bind in a syn conformation. The modular synthetic approach allows the pore to be expanded based on the aryl moiety in the center of the linker from 11.0 angstrom to 15.5 angstrom. When there is an axis of rotation, each aryl ring can act independently as a rotating gate as a function of guest molecules. For the two aryl ring system, all three states (open/open, open/closed, and closed/closed) are observed by single crystal X-ray diffraction (SCXRD). The guest dependent nature of the aryl rings makes this two-pillared topology a logical choice for breathing MOFs.