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391.
Santosh T. Kadam 《Tetrahedron》2009,65(50):10383-7310
The heterogeneous Amberlyst-15 catalyst displays efficient catalytic properties for the Friedel-Crafts reactions between an activated arenes or heteroarenes and α-amido sulfones. Various α-amido sulfones on treatment with 1,2,4-trimethoxy benzene give the Friedel-Crafts reaction products in very good yield. The reactions with heteroarenes show moderate yield of the product. The catalyst can be easily recycled without significant loss of activity. 相似文献
392.
DABCO is a very effective catalyst in the formation of 4-methoxy-5-arylethyl-1,3-dioxolan-2-ones 12 from the corresponding α-carbonatoaldehyde. Intramolecular cyclization of cyclic carbonates 12 promoted by TiCl4 affords 2-tetralones 13 containing a variety of substituents in high yields. 相似文献
393.
Denise Barbier Baudry Fanny Duris Jean Roger Desmurs 《Journal of fluorine chemistry》2003,121(2):233-238
The synthesis of lanthanum, neodymium and ytterbium bis(trifluoromethanesulfonyl)amides, named triflimidates, from acetates, carbonates and oxides is investigated. When the synthesis is performed in water, all the salts contain one molecule of water and the lanthanum and neodymium salts synthesized from the acetates also contain one molecule of acetic acid. After removal of the water and acetic acid in refluxing ethanol, the salts are obtained anhydrous but associated for lanthanum and neodymium, whereas the ytterbium salt is monomeric and volatile. When the synthesis is performed directly in ethanol, the neodymium salt contains two molecules of coordinated ethanol.In non-hazardous solvents, these triflimidates are better catalysts than the analogous triflates toward either Friedel-Crafts acylations, or Fries transpositions or Baeyer-Villiger oxidations. Unexpectedly, the cerium(IV) triflimidate catalyzes the oxidation of aromatic ketones to give the corresponding acids. 相似文献
394.
The catalytic enantioselective Friedel-Crafts alkylation reaction promoted by chiral palladium complexes is described. The treatment of indoles with γ,δ-unsaturated β-keto phosphonates under the mild reaction conditions afforded the corresponding Friedel-Crafts alkylation adducts with excellent enantioselectivities (up to 99% ee). 相似文献
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