Deprotonation of Organogermanium and Organotin Trihydrides

Inorg Chem. 2019 Dec 2;58(23):15758-15768. doi: 10.1021/acs.inorgchem.9b01822. Epub 2019 Aug 1.

Abstract

Terphenyltin and terphenylgermanium trihydrides were deprotonated in reaction with strong bases, such as LiMe, LDA, or KBn. In the solid state, the Li salts of the germate anion 4 and 4a exhibit a Li-Ge contact. In the Li salt of the dihydridostannate anion 6a, the Li cation is not coordinated at the tin atom instead an interaction of the Li cation with the hydride substituents was found. Evidenced by 1H-7Li-HOESY NMR spectroscopy the Li-salt of the deprotonated tin hydride 6a exhibits in toluene solution a contact between Li cation and hydride substituents, whereas in the 1H-7Li-HOESY NMR spectrum of the homologous germate salt 4a, no crosspeak between hydride and Li signals was found. The organodihydridogermate and -stannate react as nucleophiles with low-valent Group 14 electrophiles. Thus, three compounds were synthesized: Ar-Ë'-EH2-Ar (E', E = Sn, Ge; Pb, Ge; Pb, Sn; Ar = Ar', Ar*). Following an alternative synthesis Ar'SnH2PbAr* was synthesized in reaction between [(Ar*PbH)2] and [(Ar'SnH)4] generated in situ. In reaction between low-valent organotin hydride [(Ar*SnH)2] and organdihydridostannate [Ar*SnH2]- formation of distannate [Ar*2Sn2H3]- was found.