2693-46-1Relevant articles and documents
NMR and DFT study on onium ions derived from substituted fluoranthenes and benzo[κ]fluoranthenes
Okazaki, Takao,Adachi, Taisuke,Kitagawa, Toshikazu
, p. 464 - 471 (2013/05/22)
Fluoranthene and benzo[k]fluoranthene (3) are nonalternant polyaromatic hydrocarbons. Their derivatives, 3-acetyl, 8-acetyl, 3-nitro, and 3-aminofluoranthenes (4, 5, 7, and 8) were reacted in FSO3H/SO 2ClF and the solutions were observed by NMR measurements at low temperatures, which showed the formation of PAH-substituted onium ions. The most deshielded 13C peaks in fluoranthene frames were observed at 155.7 and 148.7 ppm for 4H+, 154.4 ppm for 5H+, 159.1 and 139.6 ppm for 7H+, and 139.7 ppm for 8H+. Distribution of the positive charges were estimated on the basis of changes in 13CNMR chemical shifts between onium ions and their corresponding parent compounds. Only limited delocalization of positive charges into the aromatic rings was found to occur. GIAO-derived NMR chemical shifts calculated by the DFT method were generally consistent with the experimental chemical shifts. DFT calculations suggested that benzo[k]fluoranthene (3) is favored to be protonated at C-3/C-7 positions. GIAO-derived NICS(1)zz were computed to elucidate aromaticity/antiaromaticity, and the results suggested that the five-membered rings are antiaromatic for cations 4H+, 7H+, 8H +, and 3aH+ (3-benzo[k]fluoranthenium ion).
Efficient method for the synthesis of N-cyclic maleamic acids and N-cyclic maleimides
-
, (2008/06/13)
Provided are methods for the synthesis of N-cyclic maleamic acids and N-cyclic maleimide derivatives, as well as N-cyclic maleamic acids and N-cyclic maleimides synthesized thereby. The method for synthesis of an N-cyclic maleamic acid involves reacting an amino group-containing N-cyclic compound with maleic anhydride in acetic acid to obtain an N-cyclic maleamic acid. An N-cyclic maleimide can be formed by adding hexamethyldisilazane to an N-cyclic maleamic acid prepared according to the above-described method, thereby cyclizing a maleamic acid site of the N-cyclic maleamic acid. The described methods allow for the products to be obtained at high yields.
Synthesis and characterization of nitro-, nitroso-, and aminofluoranthenes
Haeringen, C. J. van,Aten, N. F.,Cornelisse, J.,Lugtenburg, J.
, p. 335 - 344 (2007/10/02)
The synthesis is reported of the five mononitrofluoranthenes. 1-Nitrofluoranthene was synthesized in 20percent from fluoranthene, 2-nitrofluoranthene in 24percent from 1,2,3,10b-tetrahydrofluoranthene, 3-nitrofluoranthene in 13percent from fluoranthene and 7- and 8-nitrofluoranthene in 34percent from 1,2,3,10b-tetrahydrofluoranthene.The pure nitrofluoranthenes were converted into their nitroso and amino analogues.The nitrosopyrenes were also synthesized.Characterisation of each compound is described.
