| Institution: | 1. Department of Medical Services and Techniques, Health Services Vocational School, Muş Alparslan University, 49250 Muş, Turkey;2. Department of Chemistry, Faculty of Arts and Sciences, Muş Alparslan University, 49250 Muş, Turkey;3. Department of Chemistry, Gebze Technical University, 41400 Kocaeli, Turkey;4. Department of Chemistry, Faculty of Arts and Sciences, Hitit University, 19100 Çorum, Turkey;5. Department of Chemistry, Faculty of Science and Arts, İnönü University, 44280 Malatya, Turkey |
![></figure>S)Mn(CO)<sub>4</sub> (<strong>1</strong>) undergoes cyclocotrimerization with t-butyl propynoate to give the isomeric compounds <strong>3a</strong> und <strong>3b</strong> in a 1 : 1 ratio. Oxidation of <strong>3a</strong> and <strong>3b</strong> with (NH<sub>4</sub>)<sub>2</sub>Ce(NO<sub>3</sub>)<sub>6</sub>] gives thiophene <strong>4</strong>. Compounds <strong>3a</strong> and <strong>3b</strong> were characterized by use of MS spectrometry and IR, <sup>31</sup>P{<sup>1</sup>H}, <sup>1</sup>H, and <sup>13</sup>C{<sup>1</sup>H} NMR spectroscopy.</td>
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