Effect of chemical substitution on the construction of boroxine-based supramolecular crystalline polymers featuring B←N dative bonds

We report the mechanochemical synthesis of five single-crystalline phenylboroxine and 1,4-diazabicyclo[2.2.2]octane (DABCO) ligand-based adducts, directed by boron-nitrogen dative bonds. By tuning the electronic features of the phenylboroxines by chemical modifications (-H/-OMe/-F/-Cl/-Br) at the para-position, the formation of the resulting bicomponent adducts can be controlled to obtain molecular to 1D polymeric crystalline materials. The electrostatic and quantum topological aspects of the B←N bonds reveal the origin for the different binding modes of the boroxine-DABCO adducts yielding molecular to polymeric structures.