Addition Reactions of Tris(trimethylsilyl)germyl Radicals to Unsaturated Compounds. An EPR and Product Study

Stefania Bernardoni, Marco Lucarini, Gian Franco Pedulli, Luca Valgimigli, Vladimir Gevorgyan, Chryssostomos Chatgilialoglu

Research output: Contribution to journalArticle

25 Citations (Scopus)

Abstract

Tris(trimethylsilyl)germyl radicals, (TMS)3Ge·, thermally or photochemically generated by means of suitable radical initiators, were reacted with a number of unsaturated compounds. The preparative scale reaction of (TMS)3GeH with a variety of alkynes proceeded stereo- and regioselectively affording exclusively 2-alkenylgermanes in excellent chemical yields. In the analogous reactions with alkenes, no addition products were obtained except in the case of 4-vinylpyridine. This behavior is explained in terms of the reversibility of germyl radical addition to olefines. The reaction with arylalkenes, ketones, quinones, azines, and nitroalkanes was instead carried out in the cavity of an EPR spectrometer. In most cases the corresponding radical adducts were observed; however, quite often the intensity of the spectra was lower than expected and with azines no EPR signals could be detected. These results have been interpreted as an indication that the addition reaction of tris(trimethylsilyl)germyl radicals to multiple bonds is less exothermic than that of trialkylgermyl radicals. With some of the investigated compounds, the addition of (TMS)3Ge· is thermoneutral or even endothermic and is therefore readily reversible.

Original languageEnglish (US)
Pages (from-to)8009-8014
Number of pages6
JournalJournal of Organic Chemistry
Volume62
Issue number23
DOIs
StatePublished - Jan 1 1997
Externally publishedYes

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Unsaturated compounds
Addition reactions
Paramagnetic resonance
Quinones
Alkynes
Alkenes
Ketones
Spectrometers

ASJC Scopus subject areas

  • Organic Chemistry

Cite this

Addition Reactions of Tris(trimethylsilyl)germyl Radicals to Unsaturated Compounds. An EPR and Product Study. / Bernardoni, Stefania; Lucarini, Marco; Pedulli, Gian Franco; Valgimigli, Luca; Gevorgyan, Vladimir; Chatgilialoglu, Chryssostomos.

In: Journal of Organic Chemistry, Vol. 62, No. 23, 01.01.1997, p. 8009-8014.

Research output: Contribution to journalArticle

Bernardoni, Stefania ; Lucarini, Marco ; Pedulli, Gian Franco ; Valgimigli, Luca ; Gevorgyan, Vladimir ; Chatgilialoglu, Chryssostomos. / Addition Reactions of Tris(trimethylsilyl)germyl Radicals to Unsaturated Compounds. An EPR and Product Study. In: Journal of Organic Chemistry. 1997 ; Vol. 62, No. 23. pp. 8009-8014.
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