Cyclic 1,8-napththalenediyl compounds containing group 14 hetero atoms

Article abstract of DOI:10.1016/0022-328X(94)87197-3

Reaction of 1,8-naphthalenediylmagnesium with dimethylgermanium dichloride gave only dimethyl(1,8-naphthalenediyl) germanium (7), whereas use of 1,8-dilithionaphthalene gave a mixture of products, consisting mainly of 7 and its "dimer" 7,7,14,14-tetramethyldinaphtho<1,8-bc:1', 8'-fg><1,5> digermocin (8).The silicon analogue (12) of 8 was prepared in a two-step procedure, starting from 1,8-dilithionaphthalene and 1,1,2,2-tetrachloro-1,2-dimethyl-disilane.The molecular structures of 8 and 12 were determined by single crystal X-ray diffraction studies.Both structures are centrosymmetric.The central eight-membered rings containing the (CH3)2E moieties (E=Si, Ge) have a chair-like conformation.The naphthalene rings are quasi-coplanar and show strong out-of-plane distortions which are larger for 12 than for 8.Keywords: Naphthalenediyl; Lithium; Silicum; Germanium; Crystal structure