UEBER POLYGERMANE XIII. PERGERMA-ANALOGA VON DIOXAN Ph8Ge4X2 UND ETHYLENACETATAL Ph6Ge3X2 (X=O,S,Se)

Article abstract of DOI:10.1016/0022-328X(85)88091-8

<(Cl3CCOO)Ph2Ge>2 reacts with wet acetone to give Ph8Ge4O2, and with dry H2S to give Ph8Ge4S2.With Na2S or NaHSe, Ph4Ge2Cl2 yields Ph8Ge4S2 and Ph8Ge4Se2, respectively.Only Ph6Ge3S2 or Ph6Ge3Se2, but no Ph6Ge3O2, can be obtained from a mixture of Ph4Ge2Cl2, Ph2 GeCl2 and Na2S or NaHSe.The mass spectra show a high stability of the cations Ph6Ge3S2⁼ and Ph6Ge3Se2⁺.The 13C NMR phenyl signals for C(ipso) shift to high field in the series O, S, Se and 6-membered, 5-membered rings.The crystal structures of Ph8Ge4O2 (R=0.031) and Ph6Ge3S2 (R=0.036) have been determined.The 6-membered ring Ge4O2 has the chair conformation (total symmetry of the molecule is approximately C_2h, distances Ge-Ge 244.8(1) and Ge-O 178-179 pm, angle Ge-O-Ge 126.9(1) deg).The 5-membered ring Ge3Se2 has the half-chair conformation (total symmetry of the molecule is approximetely C2 distances Ge-Ge 241.5(1) and Ge-Se 236-237 pm).