Addition of Stable Nitroxide Radical to Stable Divalent Compounds of Heavier Group 14 Elements

Abstract

The reactions of stable cyclic dialkylgermylene 2 and dialkylstannylene 3 with 2,2,6,6-tetramethylpiperidinyl-1-oxy (TEMPO) radical (2 equiv) gave the corresponding 1:2 adducts 4 and 5, respectively, which were characterized by NMR, MS, and X-ray analyses. The kinetics of the stepwise addition of two TEMPO molecules to germylene 2 revealed that the initial addition of TEMPO to 2 was 1010 times slower than the second TEMPO addition to the resulting germyl radical. The origin of the rate difference was discussed on the basis of the qualitative perturbation theory. In contrast to the reactions of 2 and 3, the reaction of dialkylsilylene 1 with TEMPO gave an interesting 1,3-dioxadisiletane derivative.

Germanium(iii) corrole complex: reactivity and mechanistic studies of visible-light promoted N–H bond activations

“…15 The germanium center protrudes slightly (0.50Å) from the N 4 -plane of the corrole ligand, comparable with (TPFC)Ge-OH (0.48Å) and (TPFC)Ge-OCH 2 CH 3 (0.49Å).…”

Dual Character of Arduengo Carbene–Radical Adducts: Addition versus Coordination Product

“…(1)]. This behavior contrasts with that of the heavier (silicon and germanium) congeners of 1 [3,4] that yield only ring-centered addition radical adducts. Characterization of the radical products 3 a,b, and 4 c,d by EPR spectroscopy and quantum-mechanical density functional theory (DFT) calculations allow important information to be obtained about their molecular and electronic structure, the spin distribution, as well as to gain a better understanding of the nature of the C À M bond in carbene-metal complexes.…”

A Radical Approach to Hydroxylaminotrichlorosilanes: Synthesis, Reactivity, and Crystal Structure of TEMPO‐SiCl3 (TEMPO = 2,2,6,6‐Tetramethylpiperidine‐N‐oxyl)

“…TEMPO (99 %) was obtained from Sigma and used without further purification. 1 H, 13 C, and 29 Si NMR spectra were recorded with a Bruker Avance III at a Larmor frequency of 300 MHz for 1 H using TMS as reference and C 6 D 6 as solvent. Solid-state 29 Si NMR spectra were recorded at a frequency of 500 MHz and at a rotation frequency of 15 kHz.…”

“…The assignments made for 7 are based on intensity ratios obtained from 29 Si NMR spectra, in which the ratio of 7 to 1 is 1:3, which corresponds to a ratio of 2:3 in the 13 C NMR spectra. 13 …”