102553-24-2Relevant academic research and scientific papers
Reactions of Acetylenic γ-Glycols. XXXV. Synthesis, Spectral Properties and Plausible Formation Mechanism of Tetraarylcyclo-bis--cumulenes
Jasiobedzki, Wieslaw,Kujda, Jolanta,Wozniak-Kornacka, Janina,Zelechowski, Krzysztof
, p. 215 - 234 (2007/10/03)
Analogs of tetraphenylcyclo-bis-butatriene (10) with electron acceptor or electron donor substituents at para position of the phenyl rings have been obtained from corresponding symmetric acetylenic γ-glycols by treatment with hydrogen iodide in statu nascendi.The electron donor effect of the methoxy group causes that the tetraanisyl derivative (12) can be formed already during the obtaining of 1,4-diol (6) by the Grignard method (spontaneous dehydration during hydrolysis).The mechanism of formation of the title compounds has been discussed.UV/Vis, IR, 1H and 13C NMR data for substrates and products are given as well as MS data for the latter.A batochromic effect of substituents in electronic spectra was observed.A doubling of methyl groups protons signals occurs in 1H NMR spectra of diastereoisomer mixtures of acetylenic 1,4-diols.A comparison of 13C NMR spectra of the title compounds with linear -cumulenes has been made.Fragmentation of the title compounds (MS spectra) leads to corresponding divinylacetylenes (molecule splitting by half, dominating process). - Key words: -cumulenes; cyclo-bis-butatrienes; acetylenic γ-glycols; molecular spectroscopy; MS-spectra
