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1,3-Dioxopyrrolo[3,4-b]porphyrins: synthesis and chemistry
Carla M B Carvalho1, Maria G P M S Neves, Augusto C Tomé
1Department of Chemistry, QOPNA, University of Aveiro, 3810-193 Aveiro, Portugal.
Abstract:
A novel 1,3-dioxopyrrolo[3,4-b]porphyrin (2) has been synthesized in 70% yield following a [4 + 2] cycloaddition reaction of pyrrolo[3,4-b]porphyrin 1 with (1)O(2). The new imide was used as a template to other 1,3-dioxopyrrolo[3,4-b]porphyrins and to the corresponding open counterparts. The UV/vis absorption spectra of the new compounds show significant red-shifts when compared with those of the nonsubstituted analogues. The structure of an imide derivative was confirmed by single-crystal X-ray diffraction.
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