Porous substances such as metal–organic frameworks (MOFs), covalent organic frameworks (COFs) and zeolites are important materials for different applications, and several methods have been developed for their processing into device architectures. Solution processing of small molecule precursors into corresponding porous structures would be beneficial for many applications since it facilitates incorporation of the active material component into relevant devices thus reducing complexity and cost. Here we report that a non-planar saddle-shaped N-heterocycle-fused metallo-porphyrinoid forms a persistently microporous crystalline material directly from solution, which can undergo solvent exchange without loss of microporosity. The material is fo...