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The new Lewis acid–base adducts of general formula X(nad)B←NC₅H₄-C₅H₄N→B(nad)X [nad = 1,8-O₂C₁₀H_6, X = C₆H₅ (<b>2c</b>), 3,4,5-F₃-C₆H₂ (<b>2d</b>)] were synthesized in high yields via reactions of 1,8-dihydroxy naphthalene [nadH₂] and 4,4′-bipyridine with the aryl boronic acids C₆H₅B(OH)₂ and 3,4,5-F₃-C₆H₂B(OH)₂, respectively, and structurally characterized by multi-nuclear NMR spectroscopy and SCXRD. Self-assembled H-shaped Lewis acid–base adduct <b>2d</b> proved to be effective in forming thermally stable host–guest complexes, <b>2d</b> × solvent, with aromatic hydrocarbon solvents such as benzene, toluene, mesitylene, aniline, and <i>m</i>-, <i>p</i>-, and <i>o</i>-xylene. Crystallographic analysis of these solvent adducts revealed host–guest interactions to primarily occur via π···π contacts between the 4,4′-bipyridyl linker and the aromatic solvents, resulting in the formation of 1:1 and 1:2 host–guest complexes. Thermogravimetric analysis of the isolated complexes <b>2d</b> × solvent revealed their high thermal stability with peak temperatures associated with the loss of solvent ranging from 122 to 147 °C. <b>2d</b>, when self-assembled in an equimolar mixture of <i>m</i>-, <i>p</i>-, and <i>o</i>-xylene (1:1:1), preferentially binds to <i>o</i>-xylene. Collectively, these results demonstrate the ability of 1,8-dihydroxy naphthalene to serve as an effective building block in the selective self-assembly to supramolecular aggregates through dative covalent N→B bonds.