Synthesis and Reactivity of Low‐Valent Group 14 Element Compounds

The tetravalent germanium and tin compounds of the general formulae Ph*EX₃ (Ph* = C₆H₃Trip‐2,6, Trip = C₆H₂iPr₃‐2,4,6; E = Sn, X = Cl ( 1a ), Br ( 1b ); E = Ge, X = Cl ( 2 )) are synthesized by reaction of Ph*Li·OEt₂ with EX₄. The subsequent reaction of 1a , b with LiP(SiMe₃)₂ leads to Ph*EP(SiMe₃)₂ (E = Sn ( 3 ), Ge ( 4 )) and the diphosphane (Me₃Si)₂PP(SiMe₃)₂ by a redox reaction. In an alternative approach 3 and 4 are synthesized by using the corresponding divalent compounds Ph*ECl (E = Ge, Sn) in the reaction with LiP(SiMe₃)₂. The reactivity of Ph*SnCl is extensively investigated to give with LiP(H)Trip a tin(II)‐phosphane derivative Ph*SnP(H)Trip ( 6 ) and with Li₂PTrip a proposed product [Ph*SnPTrip]^– ( 7 ) with multiple bonding between tin and phosphorus. The latter feature is confirmed by DFT calculations on a model compound [PhSnPPh]^–. The reaction with Li[H₂PW(CO)₅] gives the oxo‐bridged tin compound [Ph*Sn{W(CO)₅}(μ‐O)₂SnPh*] ( 8 ) as the only isolable product. However, the existence of 8 as the bis‐hydroxo derivative [Ph*Sn{W(CO)₅}(μ‐OH)₂SnPh*] ( 8a ) is also possible. The Sn^IV derivatives Ph*Sn(OSiMe₃)₂Cl ( 9 ) and [Ph*Sn(μ‐O)Cl]₂ ( 10 ) are obtained by the oxidation of Ph*SnCl with bis(trimethylsilyl)peroxide and with Me₃NO, respectively. Besides the spectroscopic characterization of the isolated products compounds 1a , 2 , 3 , 4 , 8 , and 10 are additionally characterized by X‐ray diffraction analysis.