IPy2BF4 is also a useful reagent for stereospecific iodine-silicon exchange in open chain trimethylsilylalkenes
摘要:
Reaction of the title monosubstituted vinylsilanes with IPy(2)BF(4)/HBF4 gives iodoalkenes through the ipso-substitution process with stereospecific retention of configuration.
decarbonylative alkenylation of aromatic carboxylic acids was developed. Under the reaction conditions, various benzoic acids including those bearing functional groups coupled to terminal alkenes, producing the corresponding internal alkenes in good to high yields. Cinnamic acids and bioactive benzoic acids such as 3-methylflavone-8-carboxylic acid, probenecid, adapalin, and febuxostat were also applicable to this
Stereoselective Peterson Olefinations from Bench-Stable Reagents and<i>N</i>-Phenyl Imines
作者:Manas Das、Atul Manvar、Maïwenn Jacolot、Marco Blangetti、Roderick C. Jones、Donal F. O'Shea
DOI:10.1002/chem.201500475
日期:2015.6.8
The synthesis of bench‐stable α,α‐bis(trimethylsilyl)toluenes and tris(trimethylsilyl)methane is described and their use in stereoselective Peterson olefinations has been achieved with a wide substrate scope. Product stereoselectivity was poor with carbonyl electrophiles (E/Z ∼1:1 to 4:1) though this was significantly improved by employing the corresponding substituted N‐benzylideneaniline (up to 99:1)
The reaction proceeded via cationic species generated by the interaction of GaCl3 and silylethyne. High reactivity of the intermediate was demonstrated by the rapid reaction rate at −78 °C using close to the equimolar amount of the substrates. ipso-Substitution reaction took place with 1,2,3-trimethoxybenzene. Structures and properties of several organogalliumcompounds involved in the reactions are
在 GaCl3 存在下,甲硅烷基乙炔与芳烃发生亲电反应,得到 β-甲硅烷基乙烯化芳烃。该反应通过由 GaCl3 和甲硅烷基乙炔相互作用产生的阳离子物质进行。使用接近等摩尔量的底物,在 -78 °C 下的快速反应速率证明了中间体的高反应性。1,2,3-三甲氧基苯发生同位取代反应。讨论了参与反应的几种有机镓化合物的结构和性质。
Stereoselective one-pot synthesis of vinylsilanes from aromatic aldehydes
作者:Man Lung Kwan、Chiu W Yeung、Kerry L Breno、Kenneth M Doxsee
DOI:10.1016/s0040-4039(00)02271-1
日期:2001.2
Vinylsilanes serve as convenient vinyl anion equivalents, but procedures for their stereoselective synthesisfromaldehydes are scarce. A variety of aromatic aldehydes are converted to the corresponding vinylsilanes in a one-pot procedure involving the addition of (trimethylsilylmethyl)lithium to the aldehyde followed by treatment with Cp2TiCH2·AlMe2Cl (‘Tebbe's reagent’). Halide and alkoxide substituents