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Content available remote Pochodne porfiryn zawierające fragment acetylenowy
EN
The monograph gives a review of literature on porphyrinoids containing an ace-tylene unit attached at macrocyclic perimeter or built into a coordination core. The inclusion of an acetylene fragment provides an unusual structural motif because of its symmetrical cylindrical structure, coordination ability towards metal ions and reactivity. The synthesis, coordination properties and reactivity of porphyrin analogs with an ethynylene unit embedded in the macrocyclic skeleton have been described. Most of such macrocycles belong to stretched porphycenes and heteroporphycenes [8, 9]. The distinct class of expanded porphyrin analogs is delivered by very stable cyclooligothiophenediacetylenes with different size of the interior cavity [16]. A novel type of contracted heteroporphyrins namely dithiaethyneporphyrins, with an acetylene moiety introduced instead of one of pyrrole units, has been also characterized [17, 18]. These macrocycles display unique features of an [18]triphyrin(4.1.1) frame. The introduction of an alkyne moiety outside porphyrinic macrocycle yields meso- or B-alkynylporphyrins [38-42, 71-75]. The synthetic pathways and spectroscopic properties of alkynylporphyrins are included in the second part of the presented review. These macrocycles are widely used as building blocks in the construction of conjugated oligomeric and polymeric porphyrins and metalloporphyrins [81-85, 89-93]. Moreover, the paper provides classification of such ? conjugated systems, which are extensively explored in the analysis of charge or electron density transfer due to the strong electronic conjugation of acetylene with the [pi] system of the porphyrin ring.
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