Silaheterocycles. 26. Facile synthesis of silicon dichloro substituted 3-vinyl-1-silacyclobutanes from silene/butadiene [2+2] cycloaddition reactions: model compounds for vinylsilacyclobutane .fwdarw. silacyclohexene rearrangements

Sewald, Norbert; Ziche, Wolfgang; Wolff, Astrid; Auner, Norbert

doi:10.1021/om00034a055

Cited by 37 publications

(12 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The neopentyl silenes of Auner with chloro, alkoxy, or siloxy substituents at Si reacted with 2,3-dimethylbutadiene to give [2 + 2] and ene adducts; no [4 + 2] cycloadducts were formed [133,134]. The 1,1-dichloro substituted silene (97) is the most remarkable as 98% of its reaction with 2,3-dimethylbutadiene proceeded via [2 + 2] cycloaddition, yielding the cycloadducts 98 and 99 in similar yields (Scheme 30) [133]. Only 2% gave the ene adduct 100.…”

Section: Reactions With Dienesmentioning

confidence: 99%

Silenes: Connectors between classical alkenes and nonclassical heavy alkenes

Ottosson

Eklöf

2008

Coordination Chemistry Reviews

137

View full text Add to dashboard Cite

Section: Reactions With Dienesmentioning

confidence: 99%

Silenes: Connectors between classical alkenes and nonclassical heavy alkenes

Ottosson

Eklöf

2008

Coordination Chemistry Reviews

137

View full text Add to dashboard Cite

“…Synthesis: The derivatives, 1,1-R 2 -2,3-diphenyl-4-neopentyl-1-silacyclobut-2-enes, were prepared starting from 1,1-dichlorosilacyclobutene (1-Cl), which was synthesized according to previously published procedures [37,38] from trichlorovinylsilane, tBuLi and tolane in pentane solution. Hydrogenation of 1-Cl with LiAlH 4 in Et 2 O (at 0 8C) resulted in the precipitation of LiAlCl 4 and the formation of dihydrosilacyclobutene (1-H) in 68 % yield.…”

Section: Resultsmentioning

confidence: 99%

“…Synthesis: The derivatives, 1,1-R 2 -2,3-diphenyl-4-neopentyl-1-silacyclobut-2-enes, were prepared starting from 1,1-dichlorosilacyclobutene (1-Cl), which was synthesized according to previously published procedures [37,38] The silacyclobutenes were characterized by the usual 1 H NMR, 13 C NMR and 29 Si NMR standard procedures (see Experimental Section). The data of 1-Cl are obtained from a previous report.…”

Section: Resultsmentioning

confidence: 99%

Synthesis, Structure, Photoluminescence and Photoreactivity of 2,3‐Diphenyl‐4‐neopentyl‐1‐silacyclobut‐2‐enes

Yan

Thomson

Bäcker

et al. 2009

Chemistry A European J

Self Cite

View full text Add to dashboard Cite

A series of six 2,3-diphenyl-4-neopentyl-1-silacyclobut-2-enes with different 1,1-substituents has been prepared and characterized by single-crystal X-ray crystallography. These compounds possess a cis-stilbene-like chromophore involving also the four-membered ring, and exhibit a photophysical behavior similar to that of previously reported 1,2-diphenyl-cycloalkenes. This chromophore system is confirmed by a theoretical investigation of the electronic structure and excitation spectra. The absorption and photoluminescence of selected derivatives were studied in solution, as solid powder samples, and in doped-polymer thin films. In well-dissolved solution, the silacyclobutenes show only very weak fluorescence emission (quantum yield approximately 0.1%), due to competition with photochemical and non-radiative photophysical relaxation. When the solubility is degraded in a poor (aqueous) solvent, the formation of nanoscale aggregates leads to a significant enhancement factor in the emission intensity, due to the suppression of the photoreactivity in the more rigid molecular environment, although the quantum yield still remains below a few percent. In the solid-state, however, photoreactivity is completely suppressed leading to fluorescence quantum efficiencies of 8-23% depending on the 1,1-substituents, which demonstrates these compounds' potential as chromophores for condensed-phase luminescence applications. Two dominant competing photochemical reactions have been identified in solution (for excitation in the lowest-energy absorption band, >260 nm), which are analogous to related (sila-)cyclobutenes and stilbenoids. The first involves ring-opening due to cleavage of the 1,4-Si-C bond to form metastable silabutadienes, which was confirmed by isolating the stereospecifically formed allylsilane which results from a secondary reaction with trapping agents such as methanol or water. The second photochemical reaction involves ring closure of the 2,3-diphenyl substructure to form a dihydrophenanthrene analogue, which was confirmed by isolating the phenanthrene derivative that results following subsequent hydrogen abstraction in the presence of oxygen. Measurements of the silacyclobutenes in doped-polymer thin films reveal a spectroscopic behavior ranging from that in solution to the nano-aggregate case as the silacyclobutene dopant concentration is increased.

show abstract

“…trichloro(vinyl)silane, LitBu, and isoprene (17, 18 isomeric mixture) or 2,3-dimethylbutadiene (15). [21] The corresponding 3-ethyl-substituted derivatives 16, and an isomeric product mixture of 19 and 20 were exclusively obtained from the catalyst-supported reaction at room temperature and were isolated in high yields (ca 75%) after distillation. The fourmembered ring moieties remain stable and the same is true for the dichlorosilyl functionality (see Scheme 3).…”

Section: Introductionmentioning

confidence: 99%

ChemInform Abstract: Silaheterocycles. Part 35. Carbon=Carbon Hydrogenation of Silicon‐Functionalized Silaheterocycles.

1999

Self Cite

View full text Add to dashboard Cite

Keywords: Silanorbornenes / Silanorbornanes / Silicon-functionalized olefins / Silacyclobutanes / Hydrogenations / HeterocyclesCatalytic hydrogenation of olefins containing functionalized were prepared from the cyclopentenyl-substituted precursors 10 and 12. The 3-vinyl-substituted silacyclobutanes 15, 17, silicon groups affords the saturated products in good yields. Chloro and alkoxy substituents at the silicon atom remain and 18 were also hydrogenated in a simple apparatus with diethyl ether or THF as solvent, and Pd/C as a recoverable unaffected and, in the case of heterocyclic compounds, the cyclic or bicyclic moieties remain intact. The 2-catalyst system. A basic organosilicon compound, trichloro(vinyl)silane, is hydrogenated in a nearly silanorbornanes 4, 5, and 6 were synthesized from the corresponding 2-silanorbornenes 1, 2, and 3, and quantitative yield to form the saturated trichloro(ethyl)silane; this emphasizes the general applicability of this method. organosilanes 13 and 14 possessing the cyclopentyl group, rivatives, since the catalyst (e.g. AdamЈs platinum or

show abstract

Silaheterocycles. 26. Facile synthesis of silicon dichloro substituted 3-vinyl-1-silacyclobutanes from silene/butadiene [2+2] cycloaddition reactions: model compounds for vinylsilacyclobutane .fwdarw. silacyclohexene rearrangements

Cited by 37 publications

References 0 publications

Silenes: Connectors between classical alkenes and nonclassical heavy alkenes

Silenes: Connectors between classical alkenes and nonclassical heavy alkenes

Synthesis, Structure, Photoluminescence and Photoreactivity of 2,3‐Diphenyl‐4‐neopentyl‐1‐silacyclobut‐2‐enes

ChemInform Abstract: Silaheterocycles. Part 35. Carbon=Carbon Hydrogenation of Silicon‐Functionalized Silaheterocycles.

Contact Info

Product

Resources

About