Heterocyclic derivatives of naphthalene‐1,8‐dicarboxylic anhydride. Part I. Nitro‐7H‐benzimidazo[2,1‐a]benz[de]isoquinolin‐7‐ones

Abstract

Condensation of o‐phenylenediamine with 2‐, 3‐ and 4‐nitronaphthalene‐1,8‐dicarboxylic anhydrides gives, in each case, an isomer mixture. Separation of the mixtures into the six isomeric mononitro‐7H‐benzimidazo[2,1‐a]benz[de]isoquinolin‐7‐ones is described and the isomers characterised in respect of previously reported data on some isomers; ir and mass spectrum data are reported, the latter showing fragmentation ions which may be used in characterising dyes based on this chromophore. Other new derivatives of 7H‐benzimidazo[2,1‐a]benz[de]isoquinolin‐7‐one are also described.

Selective Preparation of Fluorescent 1,8-Naphthalimides using Acidic Alumina under Microwave Irradiation

“…10,11 In the second method, the reaction between naphthalene-1,8-dicarboxylic anhydrides and appropriately substituted o-nitroanilines produces an intermediate-N-substituted-naphthalimide, which, in a second step, can be converted into the final product by chemical reduction and condensation. 10,11 In the second method, the reaction between naphthalene-1,8-dicarboxylic anhydrides and appropriately substituted o-nitroanilines produces an intermediate-N-substituted-naphthalimide, which, in a second step, can be converted into the final product by chemical reduction and condensation.…”

“…10 The formation of the product takes place through an intermediate aminonaphthalimide stage and cyclisation of this compound can be carried out using each of the two carbonyl groups (Scheme 1). For example, Grayshan and Peters reported a 55.3/44.7 ratio of 1-to 6-nitro and 63.8/36.2 ratio of 2-to 5-nitro isomers when 1,2-phenylenediamine was reacted with 2-nitronaphthalene-1,8-dicarboxylic anhydride and 3-nitronaphthalene-1,8dicarboxylic anhydride respectively.…”

“…The first, employs the reaction between naphthalene-1,8dicarboxylic anhydride derivatives and appropriately substituted o-phenylenediamines. 10,11 In the second method, the reaction between naphthalene-1,8-dicarboxylic anhydrides and appropriately substituted o-nitroanilines produces an intermediate-N-substituted-naphthalimide, which, in a second step, can be converted into the final product by chemical reduction and condensation.…”

“…For example, Grayshan and Peters reported a 55.3/44.7 ratio of 1-to 6-nitro and 63.8/36.2 ratio of 2-to 5-nitro isomers when 1,2-phenylenediamine was reacted with 2-nitronaphthalene-1,8-dicarboxylic anhydride and 3-nitronaphthalene-1,8dicarboxylic anhydride respectively. 10 The formation of the product takes place through an intermediate aminonaphthalimide stage and cyclisation of this compound can be carried out using each of the two carbonyl groups (Scheme 1).…”

New Intermediates and Dyes for Synthetic‐polymer Fibres. Benzimidazothioxanthenoisoquinolinone Dioxides and Sulphones of 7H‐Benzimidazo (2, 1‐a) benz(d, e) isoquinolin‐7‐one

“…In these isomers the absorption maxima are related to the contribution of the diaryl system (Vc), to additional localised charge transfer interactions originating at the substituent and to perturbation effects of the substituent on the general resonance structures 1101 of the unsubstituted compound. Localised interactions originating at electronacceptor substituents are, for substitution by the electronattracting nitro group, more effective as regards colour development when present in the carbonyl-containing ring 110, 15,18], and the longer wavelength absorption of IX relative to Vlll is in accord with this, although the diaryl type interaction (cf. Vc) would be more effective in VIII.…”