10.1021/jo061659b.s003 Jamal Lasri Jamal Lasri M. Adília Januário Charmier M. Adília Januário Charmier Matti Haukka Matti Haukka Armando J. L. Pombeiro Armando J. L. Pombeiro Stereospecific Synthesis of Polysubstituted <i>E</i>-Olefins by Reaction of Acyclic Nitrones with Free and Platinum(II) Coordinated Organonitriles American Chemical Society 2007 4 b R complex Acyclic Nitrones 2R 13 C microwave irradiation 195 Pt NMR spectroscopies MeC 3C CO 2Me 1 b R oxadiazoline analyses acyclic nitrones alkene 3 refluxing CH 2Cl NC Stereospecific Synthesis 1 H CO 2Me Cl 5 c 6H CH 2Cl 5 CO 2Me NCCH FAB 1 c R IR 2007-02-02 00:00:00 Journal contribution https://acs.figshare.com/articles/journal_contribution/Stereospecific_Synthesis_of_Polysubstituted_i_E_i_Olefins_by_Reaction_of_Acyclic_Nitrones_with_Free_and_Platinum_II_Coordinated_Organonitriles/3029491 Free nitriles NCCH<sub>2</sub>R (<b>1a</b> R = CO<sub>2</sub>Me, <b>1b</b> R = SO<sub>2</sub>Ph, and <b>1c</b> R = COPh) with an acidic α-methylene react with acyclic nitrones <sup>-</sup>O<sup>+</sup>N(Me)C(H)R‘ (<b>2a</b> R‘ = 4-MeC<sub>6</sub>H<sub>4</sub> and <b>2b</b> R‘ = 2,4,6-Me<sub>3</sub>C<sub>6</sub>H<sub>2</sub>), in refluxing CH<sub>2</sub>Cl<sub>2</sub>, to afford stereoselectively the <i>E</i>-olefins (NC)(R)CC(H)R‘ (<b>3a</b><b>−</b><b>3c</b> and <b>3a</b>‘<b>−</b><b>3c</b>‘), whereas, when coordinated at the platinum(II) <i>trans</i>-[PtCl<sub>2</sub>(NCCH<sub>2</sub>R)<sub>2</sub>] complexes (<b>4a</b> R = CO<sub>2</sub>Me and <b>4b</b> R = Cl), they undergo cycloaddition to give the (oxadiazoline)-Pt<sup>II</sup> complexes (R = CO<sub>2</sub>Me, Cl and R‘ = 4-MeC<sub>6</sub>H<sub>4</sub>, 2,4,6-Me<sub>3</sub>C<sub>6</sub>H<sub>2</sub>) (<b>5a-5d</b>). Upon heating in CH<sub>2</sub>Cl<sub>2</sub>, <b>5a</b> affords the corresponding alkene <b>3a</b>. The reactions are greatly accelerated when carried out under focused microwave irradiation, particularly in the solid phase (SiO<sub>2</sub>), without solvent, a substantial increase of the yields being also observed. The compounds were characterized by IR and <sup>1</sup>H, <sup>13</sup>C, and <sup>195</sup>Pt NMR spectroscopies, FAB<sup>+</sup>-MS, elemental analyses and, in the cases of the alkene (NC)(CO<sub>2</sub>Me)CC(H)(4-MeC<sub>6</sub>H<sub>4</sub>) <b>3a</b> and of the oxadiazoline complex <b>5c</b>, also by X-ray diffraction analyses.