35947-66-1Relevant academic research and scientific papers
Sodium phenoxide-phosphine oxides as extremely active Lewis base catalysts for the Mukaiyama aldol reaction with ketones
Hatano, Manabu,Takagi, Eri,Ishihara, Kazuaki
, p. 4527 - 4530 (2007)
(Chemical Equation Presented) A highly efficient Mukaiyama aldol reaction between ketones and trimethylsilyl enolates catalyzed by sodium phenoxide-phosphine oxides as simple homogeneous Lewis base catalysts (0.5-10 mol %) was developed, which minimized c
Generation of carbanions through stibine-metal and bismuthine-metal exchange reactions and its applications to precision synthesis of ω-end-functionalized polymers
Kayahara, Eiichi,Yamada, Hiroto,Yamago, Shigeru
supporting information; experimental part, p. 5272 - 5280 (2011/06/20)
Generation of carbanions from organostibines and organobismuthines through heteroatom-metal exchange reactions was examined from synthetic and mechanistic viewpoints. The exchange reaction proceeded spontaneously upon treatment with various organometallic reagents, such as alkyl lithiums, tetraalkyl zincates, and alkyl magnesium halides to afford the corresponding carbanions quantitatively. Due to the high reactivity of these heteroatom compounds, the exchange reactions took place exclusively even in the presence of various polar functional groups, which potentially react with organometallic species. The advantage of this method was exemplified by the end-group transformation of living polymers that bear these heteroatom species at the ω-polymer end, prepared by using organostibine and bismuthine-mediated living radical polymerizations. Various polymers that bear polar functional groups and acidic hydrogen-for example, poly(methyl methacrylate), poly(butyl acrylate), poly(N-isopropyl acrylamide), and poly(2-hydroxyethyl methacrylate)-could be used in the exchange reactions, and subsequent trapping with electrophiles afforded the corresponding polymers with controlled molecular weights, molecular weight distributions, and end-group functionalities. Competition experiments showed that organostibines and organobismuthines were among the most reactive heteroatom compounds towards organometallic reagents and that their high reactivity was responsible for the high chemoselectivity in the exchange reaction. All's well that ends well: The generation of carbanions from organostibine and -bismuthine compounds was achieved thorough a heteroatom-metal exchange reaction (see scheme). The highly chemoselective exchange reaction could be applied to precision synthesis of varieties of ω-end- functionalized polymers that possess a polar functional group.
Highly efficient synthesis of functionalized tertiary alcohols catalyzed by potassium alkoxide-crown ether complexes
Hatano, Manabu,Suzuki, Shinji,Takagi, Eri,Ishihara, Kazuaki
supporting information; experimental part, p. 3171 - 3174 (2009/08/09)
A highly efficient Mukaiyama aldol reaction between ketones and trimethylsilyl enolates in the presence of potassium alkoxide-crown ether complexes as Lewis base catalysts (0.3-5 mol %), which minimized the competing retro-aldol reaction, was developed. T
Synthesis of α,α,β,β-Tetrasubstituted β-Lactones from Ketones, Ethyl α-Bromoisobutyrate, and Indium or Zinc. Factors Influencing the β-Lactone Formation in the Electrochemical and the Classical Procedure of the Reformatsky Reaction
Schick, Hans,Ludwig, Ralf,Schwarz, Karl-Heinz,Kleiner, Katharina,Kunath, Annamarie
, p. 3161 - 3164 (2007/10/02)
An efficient synthesis of α,α,β,β-tetrasubstituted β-lactones is achieved by an electrochemically supported Reformatsky reaction of aliphatic and aromatic ketones with ethyl α-bromoisobutyrate at a sacrificial indium anode.Under these conditions, in most
