0000000000221422
AUTHOR
Karl Häberle
Über polygermane
Abstract The germylene Ph2Ge of Ph2GeHCl and Net3 inserts in excess Ph2GeHCl and forms polygermanes Cl(Ph2Ge)nH. This one-pot reaction and subsequent chlorination to Cl(Ph2Ge)nCl has been optimized. Increasing amounts of NEt3 step up the yields of higher polygermanes. The 13C NMR phenyl signals for C(ipso) shift to low field with increasing chain length. The crystal structures of Cl(Ph2Ge)3,4Cl (R = 0.072 and 0.087) have been determined. The position of Cl(Ph2Ge)4Cl is split off by disorder (main molecule 82%, side molecule 18%). Two crystallographically different molecules of the trigermane are present; the ClGe3Cl chain contains anti-gauche and gauche-gauche conformation respectively (d…
Über polygermane
Abstract The optimum conditions for selectively cleaving off two phenyl groups in Ge2Ph6 by trichloroacetic acid have been determined. Neither trihaloacetic acids nor HCl/AlCl3 nor reactive tetrahalides MCl4 are suitable reagents for cleaving one phenyl group alone. The 13C NMR chemical shifts of functional phenyl-mono- and -digermanes are given. The crystal structure of 1,2-bis(trichloroacetate)tetraphenyldigermane has been determined and refined to R = 0.048. The digermane bond is bridged by both acetates (distances GeGe 239.3(2), GeO 207.3(3) and 231.4(3) pm). The Ge atoms have trigonal bipyramidal coordination.
Über polygermane
Abstract [(Cl 3 CCOO)Ph 2 Ge] 2 reacts with wet acetone to give Ph 8 Ge 4 O 2 , and with dry H 2 S to give Ph 8 Ge 4 S 2 . With Na 2 S or NaHSe, Ph 4 Ge 2 Cl 2 yields Ph 8 Ge 4 S 2 and Ph 8 Ge 4 Se 2 , respectively. Only Ph 6 Ge 3 S 2 or Ph 6 Ge 3 Se 2 , but no Ph 6 Ge 3 O 2 , can be obtained from a mixture of Ph 4 Ge 2 Cl 2 , Ph 2 GeCl 2 and Na 2 S or NaHSe. The mass spectra show a high stability of the cations Ph 6 Ge 3 S 2 + and Ph 6 Ge 3 Se 2 + . The 13 C 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 Ph 8 Ge 4 O 2 ( R = 0.031) and Ph 6 Ge 3 S 2 ( R = 0.036) have been determined. The 6-membered ring…
Synthesen und Strukturen von Ethyl‐, Propyl‐, Butyl‐ und Mesitylantimon
Die Enthalogenierung von Alkylantimondibromiden RSbBr2 (R = Et, Pr, Bu) mit Mg in THF fuhrt zu gelben Losungen, die uberwiegend die Antimonfunfringe (RSb)5 neben den Vierringen (RSb)4 enthalten. Die Trimeren (RSb)3 konnen massenspektrometrisch nachgewiesen werden. Beim Entfernen des Losungsmittels bilden sich reversibel die Polymeren (RSb)x (x » 5) in Form schwarzer Festkorper. In den Ringen nehmen die Substituenten R maximale trans-Positionen ein. Die Kristallstruktur von (MesSb)4 · Benzol enthalt linear …Sb4…Sb4…-verknupfte Cyclotetrastiban-Aren-Komplexe mit guter η6-Haptizitat des Benzolmolekuls an eines der vier Sb-Atome (Ringmitte…Sb 3.81 A, Winkel zur Flachennormale 5°). Der Sb4-Ring …