Schwermetall-π-Komplexe. IX. Die Kettenpolymere [(1,2- (CH3)2C6H4BiCl3)2], [(1,3) (CH3)2C6H4BiCl3)2] und [(1,4- (CH3)2C6H4BiCl3)2]

Heavy Metal π-Complexes. IX. The Chain Polymers [(1,2- (CH₃)₂C₆H₄BiCl₃)₂], [(1,3- (CH₃)₂C₆H₄BiCl₃)₂] and [(1,4- (CH₃)₂C₆H₄BiCl₃)₂] In the crystal structures of the three solid state complexes (C₆H₄(CH₃)₂BiCl₃ (C₆H₄(CH₃)₂ = o-xylene: 1 , m-xylene: 2 , p-xylene: 3 ) quasi-dimeric units of almost undistorted, arene coordinated BiCl₃ fragments can be found that are further associated via additional Bi? Cl contacts to form one-dimensional polymeric chains. Whereas the chains of 2 and 3 are constituted by Bi₂Cl₂ four-membered rings only, further Cl-bridging in 1 leads to additional trigonal-bipyramidal arrangements with Bi atoms exhibiting coordination numbers of 3 + 3 + 1 and 3 + 2 + 1, respectively (prim. + sec. Cl contacts + arene). The arene-metal bonding is characterized by Bi-arene distances in the range from 297 – 306 pm, including ring slippages of 24 –41 pm and 73 pm with the Bi atoms being six and seven coordinated, respectively. The direction of this slipping with respect to the arene's methylation sites cannot be understood in terms of electronic influences but is shown to be caused by steric demands. The values IP₁ of the arenes prove to determine the colours of the complexes.