Novel derivatives of hypervalent germanium: synthesis, structure, and stability

摘要

Syntheses of a series of novel germanium complexes, viz. RN(CH2CH2NC6F5)(2)GeHal(2) (1, R = Me, Hal = Cl; 2, R = Me, Hal = Br; 3, R = PhCH2, Hal = Cl; 4, R = PhCH2, Hal = Br), as well as MeN[CH2(2-C4H3N)](2)GeHal(2) (5, Hal = Cl; 6, Hal = Br), by the reaction of GeHal(4) with dilithium salts of corresponding triamines 7-9 are presented. PhCH2N(CH2CH2NSiMe3)(2)GeCl2 (10) was prepared analogously from triamine 11. Other approaches to the synthesized compounds were also tested. Unexpected complexes [N(CH2CH2NSiMe3)(2)Ge(Hal)](2) (12, Hal = Cl; 13, Hal = Br) were obtained by the reaction of GeHal(4) with dilithium salt of Me3SiN(CH2CH2NHSiMe3)(2) (14). DFT calculations on this reaction were carried out and discussed. Composition and structures of the novel compounds were established by elemental analyses, H-1, C-13, and F-19 NMR spectroscopy. The X-ray structural studies of 1-4 and 12 clearly indicated the presence of a transannular interaction N(ax)-->Ge for all studied compounds.