7299-46-9Relevant academic research and scientific papers
Microwave Spectra of Trimethylsilylethyne, Me3SiCCH, 1-Cyano-2-trimethylsilylethyne, Me3SiCCCN, and 1-Cyano-4-trimethylsilylbutadiyne, Me3Si(CC)2CN
Alexander, Anthony J.,Firth, Steven,Kroto, Harold W.,Walton, David R. M.
, p. 531 - 534 (1992)
The microwave spectra of the title compounds, recorded in the 26.5-40.0 GHz region, are characteristic of symmetric top molecules, complicated by internal rotation and accompanied by vibrational satellites attributed to low-frequency skeletal bending modes.For Me3SiCCH, B0 = 1962.163 MHz and relative intensity measurements on the vibrational satellites give a value of 110 +/- 15 cm-1 for the degenerate Si-CC bending mode.Measurements on Me3SiCCD have been made, and the Si-C bond length has been determined as 1.83 +/- 0.01 Angstroem.For Me3SiCCCN, B0 = 711.8646MHz, whilst for Me3Si(CC)2CN, twenty broad-band symmetric-top transitions, from J = 41 to 60, have been observed and a B value of 331 +/- 2 MHz has been estimated.
Reactions of five-membered zirconacycloalkynes and zirconacycloallenes with Cp2Zr(H)Cl; Formal hydrogenation by metal hydrides
Ban, Sayaka,Ito, Saki,Mochizuki, Ayari,Suzuki, Noriyuki
supporting information, p. 16265 - 16272 (2021/11/30)
Reactions of five-membered zirconacycloalkynes and zirconacyloallenes (1-zirconacyclopent-3-ynes and 1-zirconacyclopenta-2,3-dienes) with an excess of Cp2Zr(H)Cl, known as the Schwartz reagent, were studied. Both reactions gave five-membered zirconacycloalkenes, 1-zirconacyclopent-3-enes without subsequent work-up such as protonolysis and hydrogenolysis. The product was identical to the zirconocene-diene complex that was prepared from Cp2Zr(n-Bu)2 (Negishi reagent) and the corresponding 1,4-disubstituted 1,3-dienes. These results indicate that formal hydrogenation by metal hydride took place. The use of diisobutylaluminum hydride or 9-borabicyclo[3.3.1]nonane also gave the same product, albeit in lower yields. The reactions starting from deuterated compounds suggested that double hydrozirconation followed by elimination of a dinuclear zirconium complex resulted in the hydrogenated products.
Selective Oligomerization and [2 + 2 + 2] Cycloaddition of Terminal Alkynes from Simple Actinide Precatalysts
Batrice, Rami J.,McKinven, Jamie,Arnold, Polly L.,Eisen, Moris S.
, p. 4039 - 4050 (2015/09/01)
A catalyzed conversion of terminal alkynes into dimers, trimers, and trisubstituted benzenes has been developed using the actinide amides U[N(SiMe3)2]3 (1) and [(Me3Si)2N]2An[κ2-(N,C)-CH2Si(CH3)N(SiMe3)] (An = U (2), Th (3)) as precatalysts. These complexes allow for preferential product formation according to the identity of the metal and the catalyst loading. While these complexes are known as valuable precursors for the preparation of various actinide complexes, this is the first demonstration of their use as catalysts for C-C bond forming reactions. At high uranium catalyst loading, the cycloaddition of the terminal alkyne is generally preferred, whereas at low loadings, linear oligomerization to form enynes is favored. The thorium metallacycle produces only organic enynes, suggesting the importance of the ability of uranium to form stabilizing interactions with arenes and related π-electron-containing intermediates. Kinetic, spectroscopic, and mechanistic data that inform the nature of the activation and catalytic cycle of these reactions are presented. (Chemical Equation Presented).
Reactivity of individual organolithium aggregates: A RINMR study of n-butyllithium and 2-methoxy-6-(methoxymethyl)phenyllithium
Jones, Amanda C.,Sanders, Aaron W.,Bevan, Martin J.,Reich, Hans J.
, p. 3492 - 3493 (2008/01/01)
Low-temperature rapid injection NMR (RINMR) experiments were performed on two lithium reagents, n-butyllithium and 2-methoxy-6-(methoxymethyl)phenyllithium (5), with the goal of measuring the relative reactivity of the different aggregates (dimer, mixed dimer, and tetramer for n-BuLi, monomer and tetramer for 5) toward typical electrophiles. The reaction of the n-BuLi dimer with (trimethylsilyl)acetylene first forms the mixed dimer n-BuLi·Me3SiC≡CLi, which is about 1/60 as reactive as the n-BuLi homodimer. The tetramer does not react. In the deprotonation of (phenylthio)acetylene, the n-BuLi dimer was found to be 3.5 × 108 as reactive as the tetramer, and in the addition to p-diethylaminobenzaldehyde, the relative reactivity was at least 2 × 104. In the deprotonation of (p-tolylsulfonyl)acetylene, the monomer of 5 was at least 1014 times as reactive as the tetramer. These measurements show that the difference in reactivity between the lower and higher aggregates of organolithium reagents can be many orders of magnitude higher than all previous estimates. Copyright
The mechanism of [2 + 1] and [2 + 2] cycloaddition reactions of 1-phenylseleno-2-(trimethylsilyl)ethene: An isotopic labelling study
Yamazaki, Shoko,Yanase, Yuichiro,Yamamoto, Kagetoshi
, p. 1991 - 1996 (2007/10/03)
The reactions of deuterio-labelled 1-seleno-2-sitylethenes with trimethyl 2-phosphonoacrylate 2 and methyl vinyl ketone 4 in the presence of SnCl4 gave deuterio-substituted cyclopropanes with 1,2-silicon migration. The reaction of deuterio-labe
