Benzo[f]isoindole derivatives from cycloaddition reaction of 2,4-dimethylpyrimido[2,1-a]isoindole and maleimides

Synthesis and Fluorescence Properties of 4-aminobenzo[f]Isoindole Derivatives

“…16 We noticed that a small amount of a substance having strong blue fluorescence was also obtained. Analysis of the data 12 and the newly acquired data proved the fluorescent product to be a derivative of benzo[f]isoindole. Formation of this compound provided evidence that the reaction involves formation of the Diels-Alder cycloaddition product which can transform into either the bis-Michael adduct 5 (when the C-C bond is cleaved) or the adduct 4 (when a molecule of ammonia is eliminated).…”

“…12 In the current research, we developed a new synthetic route to the latter compounds, giving better yields and easier to implement than the existing one. 12 The structures of the substances synthesised were confirmed by spectral methods and X-ray crystal analysis. Absorption and fluorescence spectra were recorded and it was noted that these spectral data are highly dependent upon substituents and on the water content in organic solvents.…”

“…Diels-Alder adducts derived from fused azino-and azoloisoindoles with maleimides undergo further rearrangements and form compounds with addends in both a 1:1 and 1:2 ratio, that possess intriguing properties. [9][10][11][12] Reaction of 2,4-dimethylpyrimido[2,1-a]isoindole with a variety of maleimides gives derivatives of 4-aminobenzo[f] isoindole which exhibit notably strong fluorescence. 12 In the current research, we developed a new synthetic route to the latter compounds, giving better yields and easier to implement than the existing one.…”

“…[9][10][11][12] Reaction of 2,4-dimethylpyrimido[2,1-a]isoindole with a variety of maleimides gives derivatives of 4-aminobenzo[f] isoindole which exhibit notably strong fluorescence. 12 In the current research, we developed a new synthetic route to the latter compounds, giving better yields and easier to implement than the existing one. 12 The structures of the substances synthesised were confirmed by spectral methods and X-ray crystal analysis.…”

The Curtin–Hammett principle in action: 1-amino-3H-isoindole in cycloaddition reactions

“…Isoindoles are promising active biological materials 1,2 with interesting spectral properties and are the subject of study for important theoretical questions, such as: aromaticity, tautomerism [3][4][5][6][7][8] and represent the important source of the reactive compounds and synthons used for cycloaddition reactions, [9][10][11][12][13][14] the study of the organic reactions mechanisms, new rearrangements [15][16][17][18][19][20][21] and the creation of new colouring agents. [22][23][24] The most typical reaction for simple isoindole systems is the Diels-Alder reaction but previously this reaction was associated only with isoindoles prevalently in the isoindole tautomeric form.…”