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• 194997-77-8 Ni(CCSi(C₆H₅)3)(P(CH₃)3)2(C(CCSi(CH₃)3)C(Si(CH₃)3)(CCSi(CH₃)3)) 

Relevant academic research and scientific papers

Nickel-mediated synthesis of dialkynyl and trialkynyl ethenes - Demetallation reactions

Metalorganic syntheses of the title compounds starting from 1-alkynes and Ni(cod)(PMe3)2 or Ni(PMe3)4 consist of less than six steps and afford better than 50% overall yields of isolated compounds. Elimination of the metal by reductive C,C coupling in diorganonickel complexes under 1 bar CO and workup in aqueous hydrochloric acid are the key steps in the preparation of (RC≡C)R′C=C(R)(C≡CR) (R=SiMe3, CMe3; R′=H, CH3, C6H5, C≡CH, C≡CCH3, C≡CCMe3, C≡CSiMe3, C≡CSiPh3, C≡CC6H5, C≡CC6H4F, C≡CC6H11, C≡CCH2SiMe3). Starting from 3-bromopropyne the initial C,C-coupling reaction is followed by an oxidative addition of the CH2Br function to zerovalent nickel and a second C,C coupling, which generates the tetradecadienetetrayne skeleton of (RC≡C)(R)C=(RC≡C)C-C≡C-CH2-CH 2-C≡C-(RC≡C)C=C(C≡CR)-(R)(R=SiMe3).