Investigation of Silver Salt Metathesis: Preparation of Cationic Germanium(II) and Tin(II) Complexes, and Silver Adducts Containing Unsupported Silver−Germanium and Silver−Tin Bonds

Syntheses of halide derivatives of germanium(II) and tin(II) aminotroponiminate (ATI) complexes and their silver
salt metathesis reactions have been investigated. The treatment of GeCl2·(1,4-dioxane), SnCl2, or SnI2 with
[(n-Pr)2ATI]Li in a 1:1 molar ratio affords the corresponding germanium(II) or tin(II) halide complex [(n-Pr)2ATI]MX
(where [(n-Pr)2ATI]- = N-(n-propyl)-2-(n-propylamino)troponiminate; M = Ge or Sn; X = Cl or I). As usually
expected, [(n-Pr)2ATI]GeCl and [(n-Pr)2ATI]SnCl undergo rapid metathesis with CF3SO3Ag, leading to trifluoromethanesulfonate salts, {[(n-Pr)2ATI]Ge}[SO3CF3] and {[(n-Pr)2ATI]Sn}[SO3CF3], and silver chloride. However,
when the silver source [HB(3,5-(CF3)2Pz)3]Ag(η2-toluene) is used, rather than undergoing metathesis, very stable
1:1 adducts [HB(3,5-(CF3)2Pz)3]Ag←Ge(Cl)[(n-Pr)2ATI] and [HB(3,5-(CF3)2Pz)3]Ag←Sn(Cl)[(n-Pr)2ATI] are formed
(where [HB(3,5-(CF3)2Pz)3]- = hydrotris(3,5-bis(trifluoromethyl)pyrazolyl)borate). The use of the iodide derivative
[(n-Pr)2ATI]SnI did not change the outcome either. All new compounds have been characterized by multinuclear
NMR spectroscopy and X-ray crystallography. The Ag−Ge and Ag−Sn bond distances of [HB(3,5-(CF3)2Pz)3]Ag←
Ge(Cl)[(n-Pr)2ATI], [HB(3,5-(CF3)2Pz)3]Ag←Sn(Cl)[(n-Pr)2ATI], and [HB(3,5-(CF3)2Pz)3]Ag←Sn(I)[(n-Pr)2ATI] are
2.4142(6), 2.5863(6), and 2.5880(10) Å, respectively. A convenient route to [(n-Pr)2ATI]H is also reported.