This work describes a three-step chromatography-free protocol for the synthesis of a novel organic materials building block, dichlorinated mellophanic diimide (MDI), that is shown to undergo nucleophilic substitution with a variety of ortho disubstituted benzenes to yield a series of chromophores. Furthermore, 1,2,4,5-tetrasubstituted benzenes can be used to synthesize tetraimide heteropentacene derivatives endcapped by MDI motifs. The fine-tuning effects of heteroatom identity were investigated by UV−vis and fluorescence spectroscopy, cyclic and differential pulse voltammetries, and density functional theory calculations. Oxidation of diamino MDI derivatives yields di-and tetraimide functionalized azaacenes with significantly lowered LUMO levels (down to −4.49 eV), narrowed band gaps (down to 1.81 eV), and high molar absorptivities (up to 84,000 M −1 cm −1 ).

The preparation of halogenated benzene-1,2,3,4-tetracarboxylic diimide derivatives is challenging because of the possibility of competitive incorrect cyclizations and SNAr reactivity. Here, we demonstrate that bypassing traditional cyclic anhydrides and instead directly reacting dihalobenzene-1,2,3,4-tetracarboxylic acids with primary amines in acetic acid solvent successfully provides a range of desirable ortho-diimide products in good yields. Furthermore, we demonstrate that sterically challenging N-derivatizations can be readily achieved under microwave reactor conditions. The halogenated diimides described here are attractive building blocks for organic materials chemistry.

The preparation of halogenated benzene-1,2,3,4-tetracarboxylic diimide derivatives is challenging because of the possibility of competitive incorrect cyclizations and SNAr reactivity. Here, we demonstrate that the direct reaction of benzene-1,2,3,4-tetracarboxylic acids with primary amines in acetic acid solvent successfully provides a range of desirable ortho-diimide products in good yields. Furthermore, we demonstrate that sterically challenging N-derivatizations can be readily achieved under microwave reactor conditions, and that SNAr reactivity is only observed when excess amine is used. The halogenated diimides described here are attractive building blocks for organic materials chemistry.

This work describes a three-step chromatography-free protocol for the synthesis of a novel organic materials building block, dichlorinated mellophanic diimide (MDI), that is shown to undergo nucleophilic substitution with a variety of ortho disubstituted benzenes to yield a series of chromophores. Furthermore, 1,2,4,5tetrasubstituted benzenes can be used to synthesize tetraimide heteropentacene derivatives endcapped by MDI motifs. The fine-tuning effects of heteroatom identity were investigated by UV-Vis and fluorescence spectroscopy, cyclic and differential pulse voltammetries, and density functional theory calculations. Oxidation of diamino MDI derivatives yields di-and tetraimide functionalized azaacenes with significantly lowered LUMO levels (down to -4.49 eV), narrowed bandgaps (down to 1.81 eV), and high molar absorptivities (up to 84,000 M -1 cm -1 ).

This work describes a three-step chromatography-free protocol for the synthesis of a novel organic materials building block, dichlorinated mellophanic diimide (MDI), that is shown to undergo nucleophilic substitution with a variety of ortho disubstituted benzenes to yield a series of chromophores. Furthermore, 1,2,4,5tetrasubstituted benzenes can be used to synthesize tetraimide heteropentacene derivatives endcapped by MDI motifs. The fine-tuning effects of heteroatom identity were investigated by UV-Vis and fluorescence spectroscopy, cyclic and differential pulse voltammetries, and density functional theory calculations. Oxidation of diamino MDI derivatives yields di-and tetraimide functionalized azaacenes with significantly lowered LUMO levels (down to -4.49 eV), narrowed bandgaps (down to 1.81 eV), and high molar absorptivities (up to 84,000 M -1 cm -1 ).