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 GeCl(2) x (1,4-dioxane), SnCl(2), or SnI(2) with (n-Pr)(2)ATI]Li in a 1:1 molar ratio affords the corresponding germanium(II) or tin(II) halide complex (n-Pr)(2)ATI]MX (where (n-Pr)(2)ATI](-) = N-(n-propyl)-2-(n-propylamino)troponiminate; M = Ge or Sn; X = Cl or I). As usually expected, (n-Pr)(2)ATI]GeCl and (n-Pr)(2)ATI]SnCl undergo rapid metathesis with CF(3)SO(3)Ag, leading to trifluoromethanesulfonate salts, (n-Pr)(2)ATI]Ge]SO(3)CF(3)] and (n-Pr)(2)ATI]Sn]SO(3)CF(3)], and silver chloride. However, when the silver source HB(3,5-(CF(3))(2)Pz)(3)]Ag(eta(2)-toluene) is used, rather than undergoing metathesis, very stable 1:1 adducts HB(3,5-(CF(3))(2)Pz)(3)]Ag<--Ge(Cl)(n-Pr)(2)ATI] and HB(3,5-(CF(3))(2)Pz)(3)]Ag<--Sn(Cl)(n-Pr)(2)ATI] are formed (where HB(3,5-(CF(3))(2)Pz)(3)](-) = hydrotris(3,5-bis(trifluoromethyl)pyrazolyl)borate). The use of the iodide derivative (n-Pr)(2)ATI]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-(CF(3))(2)Pz)(3)]Ag<-- Ge(Cl)(n-Pr)(2)ATI], HB(3,5-(CF(3))(2)Pz)(3)]Ag<--Sn(Cl)(n-Pr)(2)ATI], and HB(3,5-(CF(3))(2)Pz)(3)]Ag<--Sn(I)(n-Pr)(2)ATI] are 2.4142(6), 2.5863(6), and 2.5880(10) A, respectively. A convenient route to (n-Pr)(2)ATI]H is also reported.