Zur oxidativen Addition von 1-Halogenalk-1-inen – Synthese und Struktur von Phenylalkinylpalladium-Komplexen

On the Oxidative Addition of 1-Halogenalk-1-ynes – Synthesis and Structure of Phenylalkynylpalladium Complexes Pd(PPh₃)₄] ( 2 ) reacts with IC≡CPh and ClC≡CPh in the sense of an oxidative addition to give trans-Pd(C≡CPh)X(PPh₃)₂] (X = I: 3 a , X = Cl: 3 b ). As side products trans-PdX₂(PPh₃)₂] (X = I: 4 a , X = Cl: 4 b ; < 10%) and PhC≡C–C≡CPh ( 5 ; X = I: ca 30%, X = Cl: < 4%) are formed. 3 a and 3 b were characterized by NMR (¹H, ¹³C, ³¹P) and IR spectroscopies as well as by X-ray single-crystal structure analyses. In the crystals of 3 a and 3 b isolated molecules were found. The Pd–C≡C–Ph unit is linear in 3 a and approximately linear in 3 b Pd–C≡C 174.2(6)°, C≡C–C 179,0(7)°].