Preparation and reactions of samarium diiodide in nitriles
作者:Béatrice Hamann、Jean-Louis Namy、Henri B. Kagan
DOI:10.1016/0040-4020(96)00861-7
日期:1996.11
Samarium diiodide can be prepared from samarium metal in various nitriles. Because of its chemical inertness pivalonitrile is the most suitable solvent. Organic reactions mediated by SmI2 are slower than in THF, but selectivities are often improved. Reactions are greatly accelerated by addition of catalytic amounts of some transition metal salts.
Concise syntheses of 3-methylenetetrahydrofuran-2-one derivatives and related systems
作者:Robert M. Adlington、Anthony G. M. Barrett
DOI:10.1039/p19810002848
日期:——
Using the Shapiro reaction, the title compounds were prepared in ‘one pot’ from the condensation of two ketones, or an aldehyde and a ketone, with carbon dioxide. For example, acetone 2,4,6-tri-isopropylbenzenesulphonylhydrazone was treated in sequence with n-butyl-lithium (–50 °C), acetone (–50 °C), n-butyl-lithium (–78 to 0 to –78 °C), carbon dioxide (–78 °C), and trifluoroacetic acid (25 °C) to