Dinuclear organotin compounds carrying naphthylene- and biphenylene-spacer groups

The reaction of XMg-CH2-Y-CH2-MgX [Y = 2,6-naphthylene (-C10H6-) or 1,1'-biphenylene (-C12H8-); X = Cl or Br] with two molar equivalents of Ph3SnCl or Ph-2(Me3SiCH2)SnI gave Ph3Sn-CH2-C10H6-CH2-SnPh3 (1), Ph3Sn-CH2-C12H8-CH2-SnPh3 (2) and Ph-2(Me3SiCH2)Sn-CH2- C12H8-CH2-Sn(CH2SiMe3)Ph-2 (3), respectively, in good yields. Reaction of 2 with elemental iodine gave, via selective Sn-Ph bond cleavage, the corresponding bis(iododiphenylstannyl) derivative Ph2ISn-CH2- C12H8-CH2-SnIPh2 (4) and iodobenzene. Compounds 1-4 were characterized by spectroscopic methods, mass spectrometry and single-crystal X-ray diffraction analysis. The tin centers in 1-3 exhibit tetrahedral coordination geometries, both in solution and the solid state. For the bis(iododiphenylstannyl) derivative 4, the tin atoms show tetrahedral geometries only in solution, as deduced from the Sn-119 NMR spectra. In the solid state, the metal atoms have distorted trigonal-bipyramidal environments as result of intermolecular I/Sn donor-acceptor interactions. In consequence, the crystal structure of 4 is composed of 2D coordination polymers, which are reinforced by C-H center dot center dot center dot I and C-H center dot center dot center dot pi contacts. (C) 2020 Elsevier B.V. All rights reserved.