Electrochemical Reactivity and Anodic Cyanation of Germatranes

Abstract

The electrooxidation of germatranes with different R groups at Ge was studied in CH3CN and DMF solutions. The results of cyclic voltammetry supported by DFT B3LYP/6-311G calculations suggest that donor activity of the N atom is substantially reduced by the dative N-Ge coordination compared to parent trialkylamino derivatives, Et3N and (HOCH2CH2)3N. The electro chemical reactivity of these compounds is well described by the generalized additive inductive model including mesomeric interactions. The oxidation of germatranes follows classical scheme for tertiary amines - reversible electron transfer with the ensuing deprotonation of alpha-carbon atom; last reaction was used for anodic cyanation of m-bromobenzyl germatrane.

Novel Stannatranes of the Type N(CH2CMe2O)3SnX (X = OR, SR, OC(O)R, SP(S)Ph2, Halogen). Synthesis, Molecular Structures, and Electrochemical Properties

“…No such data exist for the chloridosubstituted germatrane N(CH 2 CH 2 O) 3 GeCl but one can expect even higher E p since germatranes are more difficult to oxidize than silatranes. 46,51 From a simple correlation of E p with calculated IPs of the stannatranes 4, 8, and 13, the oxidation potential of the chlorido-substituted derivative 13 should be above 2.3 V which corroborates the results of its voltammetry.…”

“…Thus the cation radical, hereafter referred to as CR, of stannatrane 4 has the spin distribution as an O-substituted t-Bu-phenoxy radical and not as a proper metallatrane, similarly to the cation radicals of germatranes in which the 1-substituent has lower own ionization potential than the atrane nitrogen atom. 51 DFT Calculations. The geometry of the stannatranes 4, 8, and 13 and of their cation radicals was optimized using a combined treatment: primary adjustment was done at HF/6-311G level, and then the structure was optimized at DFT B3LYP/ DGDZVP level, better accounting for long-term and delocalizing electronic interactions.…”

“…In general, the presence of d-metals often results in strong spin–orbital interactions broadening the spectral lines and making it difficult to observe well resolved hyperfine structure. Thus the cation radical, hereafter referred to as CR, of stannatrane 4 has the spin distribution as an O-substituted t -Bu-phenoxy radical and not as a proper metallatrane, similarly to the cation radicals of germatranes in which the 1-substituent has lower own ionization potential than the atrane nitrogen atom …”

Radical anions of hypervalent silicon compounds: 1-substituted silatranes

“…However, their generation would be of considerable interest. The study of the structure and the spin density distribution in I À would undoubtedly contribute to the construction of a theory of structure of the open-shell compounds of Si V (and neighbors of Si in group 14), and to the development of original approaches to the synthesis of new organosilicon compounds, including I.…”

“…Note that it was reported not only for the radical cations of silatranes, [6][7][8][9][10] but also for the radical cations of their close analogues -germatranes and stannatranes. [13][14][15][16][17] However, the data for the radical anions of germatranes and stannatranes, as in the case of the RA of silatranes, are absent in the literature.…”