{"id":10678,"date":"2022-11-04T15:48:08","date_gmt":"2022-11-04T14:48:08","guid":{"rendered":"https:\/\/www.icpf.cas.cz\/?p=10678"},"modified":"2022-11-04T16:15:39","modified_gmt":"2022-11-04T15:15:39","slug":"synthesis-of-2-phospha7helicene-a-helicene-containing-a-phosphinine-core","status":"publish","type":"post","link":"https:\/\/www.icpf.cas.cz\/en\/synthesis-of-2-phospha7helicene-a-helicene-containing-a-phosphinine-core\/","title":{"rendered":"Synthesis of 2-phospha[7]helicene, a helicene containing a phosphinine core"},"content":{"rendered":"

Helical polyaromatic substances, helicenes, attract attention due to their extraordinary optoelectronic properties, which predestinate them for applications in the field of materials engineering.<\/span><\/span> However, ideal properties are rarely found in unsubstituted carbohelicenes, and it is therefore necessary to further modify these substances.<\/span><\/span> In this work, a new method was developed by which an unusual phosphinine (phosphabenzene) ring can be introduced into the helicene structure.<\/span><\/span><\/span><\/p>\n

Phosphahelicene (4-Phenyl-6-methyl-2-phospha[7]helicene) was prepared from starting 2\u2011bromobenzo[c<\/em>]phenanthrene in 12 synthetic steps in a total yield of 12%.<\/span><\/span> In the described synthesis, the appropriate helicene precursor bearing an alkyne function is first prepared.<\/span><\/span> The key step of the developed synthetic strategy is the acid-initiated cyclization of this alkyne yielding an ortho<\/em>-condensed phosphorus heterocycle, which is subsequently aromatized to form the target molecule.<\/span><\/span> The structure of the first phosphahelicene with a terminal phosphinine ring was confirmed by X-ray analysis and the basic optical properties of this compound were subsequently investigated.<\/span><\/span><\/span><\/p>\n

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Synthesis of 4-phenyl-6-methyl-2-phospha[7]helicene<\/span><\/span><\/span><\/em><\/strong><\/p>\n

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