Synthesis of tricyclic 1,4-dihydro-1,4-phosphagermines - trying to establish molecular fencing of reactive centers.

Novel tricyclic 1,4-dihydro-1,4-phosphagermines (3a and 4a) were synthesised from Ge(NR)-bridged 1,3-imidazole-2-thione derivative 2a; all structures were crystallographically confirmed. In going from rather small alkyl substituents (Me, Bu) at the nitrogen centers of the 1,3-imidazole-2-thione units to sterically more demanding R = Mes and changing the employed Ge reagent from (RN)GeCl to RNGeCl we achieved access to mixed functional bis(1,3-imidazole-2-thione)-substituted germanium derivative 2c. The latter was treated with MeLi and, subsequently, with PCl to yield a pentacyclic P,Ge-heterocycle (5); its formation was rationalized using DFT theoretical calculations.

The Preparation of Complexes of Germanone from a Germanium μ-Oxo Dimer.

Complexes of germanone containing formal Ge=O→M bonds (M=Zn, B, Ge, Sn) were isolated and characterized. The compounds were prepared through a novel synthetic route using a germanium μ-oxo dimer 3 as the starting material. This method circumvents the need to employ germanones to prepare complexes of germanones.

O,S-Heterocyclic stannylenes: synthesis and reactivity.

Commercially available N-oxide (2-mercaptopyridine-N-oxide) is used as a ligand instead of an oxidizing agent to stabilize the compounds of main group elements in low-valent states. The isolated compounds [(C5H4NOS)2Sn (), (C5H4NOS)SnCl () and (C5H4NOS)GeCl ()] are the first structurally characterized examples of O,S-heterocyclic stannylenes and germylenes with interesting bonding features. Further, the reaction of compound with SbCl3 afforded the rare dichlorodiantimony oxide [{(C5H4NOS)SbCl}2O] () unprecedentedly.

Digermylene Oxide Stabilized Group 11 Metal Iodide Complexes.

Use of a substituted digermylene oxide as a ligand has been demonstrated through the isolation of a series of group 11 metal(I) iodide complexes. Accordingly, the reactions of digermylene oxide [{(i-Bu)2ATIGe}2O] (ATI = aminotroponiminate) (1) with CuI under different conditions afforded [({(i-Bu)2ATIGe}2O)2(Cu4I4)] (2) with a Cu4I4 octahedral core, [({(i-Bu)2ATIGe}2O)2(Cu3I3)] (3) with a Cu3I3 core, and [{(i-Bu)2ATIGe}2O(Cu2I2)(C5H5N)2] (4) with a butterfly-type Cu2I2 core. The reactions of compound 1 with AgI and AuI produced [({(i-Bu)2ATIGe}2O)2(Ag4I4)] (5) with a Ag4I4 octahedral core and [{(i-Bu)2ATIGe}2O(Au2I2)] (6) with a Au2I2 core, respectively.

Single-step conversion of silathiogermylene to germaacid anhydrides: unusual reactivity.

A novel silathiogermylene [Bu(I)2(ATI)GeSSiMe3] (2) containing a reactive Ge(II)-SSiMe3 moiety showed an unusual reaction when treated with elemental selenium and sulfur to afford the germaacid anhydrides [{Bu(I)2(ATI)Ge(Se)}2Se] (3) and [{Bu(I)2(ATI)Ge(S)}2S] (4) in excellent yields, respectively. This single-step conversion of compound 2 to compounds 3 and 4 involves condensation along with insertion and oxidative addition reactions and such reactivity of a germylene with elemental chalcogens is observed for the first time.

Can low-valent germanium chemistry be practiced under ambient conditions? A tale of a water-stable yet reactive germylene monochloride complex.

A germylene monochloride complex ((DPM)GeCl, 1) that is water stable was isolated for the first time. Interestingly, it reacts with cesium fluoride under ambient conditions (non-inert atmosphere and water-containing solvent) to afford water stable germylene monofluoride complex ((DPM)GeF, 2). Due to the usage of DPM (dipyrrinate) ligand, germylene monohalides 1 and 2 show fluorescence in the visible region at 555 and 538 nm, respectively.