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Convenient Formal Synthesis of (+)-Grandisol through Promoted Lewis Acid Promoted Enantioselective Pinacolic Rearrangement
No full textReaction of N-1-acylacetamidrazones with trifluoroacetylvinyl ethers. Synthesis of new 4-trifluoromethyl- and 6-trifluoromethylpyridines
No full textThe reaction between N-1-acylacetamidrazones 1 and enol ether 2 is described. Depending on the reaction conditions and on the substitution pattern of amidrazones 2-acylhydrazino-4-methyl-6-trifluoromethylpyridines 3 and/or 2-acylhydrazino-6-methyl-4-trifluoromethylpyridines 4 were obtained
New trifluoromethylated pyridines from functionalized N-1-acylacetamidrazones
No full textPolyfunctionalized trifluoromethylpyridines 4, 5 were readily synthesized from trifluoroacetylvinyl ether 3, using N-1-acylacetamidrazones 1, 2 as starting material
A facile synthesis of 3,5-diaminopyrazole-4-carbothioamides and 3,5- diaminopyrazole-4-carboxylates
No full textSimple and convenient synthesis of hitherto unknown 3,5-diaminopyrazole- 4-carbothioamides 3 as well as new ethyl 3,5-diaminopyrazole-4-carboxylates 7 is reported. The key intermediates were 2-cyanopropenethioamides 2 and 2- (ethoxycarbonyl)propenethioamides 5 which were readily obtained by reaction of phenyl isothiocyanate with 3-(2-acylhydrazino)-3-aminopropenenitriles 1 and ethyl 3-(2-acylhydrazino)-3-aminopropenoates 4 respectively. Intramolecular cyclization of compounds 2 afforded pyrazole-4-carbothioamides 3 while propenethioamides 5 gave pyrazole-4-carboxylates 7
2,2-Dimethyl cyclopentanones by acid catalyzed ring expansion of isopropenylcyclobutanols. A short synthesis of (+/-)-alpha-cuparenone and (+/-)-herbertene
No full text2,2-Dimethyl cyclopentanones are readily prepared by acid catalyzed ring expansion of isopropenylcyclobutanols; the method allows ready access to the family of sesquiterpenes cuparanes and herbertanes, as demonstrated by the synthesis of (+/-)-alpha-cuparenone and the direct precursor of (+/-)-herbertene
Facile synthesis of 2,2-dimethylchromans by Mo(CO)(6) catalyzed reaction of aryl prenyl ethers
No full text2,2-Dimethylchromans 3a-g are synthesized in good yields by a one-pot reaction of the aryl prenyl ethers 1a-g with a catalytic amount of Mo(CO)(6) in refluxing toluene
A new and efficient synthesis of phthalazin-1(2H)-ones
No full text2-Amino-2-(aroylhydrazono)ethyl aryl ethers, readily obtained from a wide range of aryloxyacetonitriles, are converted to phthalazin-1(2H)-ones derivatives in high yields by heating in PrOH in the presence of p-TsOH
Tetrazole Amides as Hydrogen-Bonding Donor Catalysts in the Chemoselective Oxidation of Sulphides and Disulphides
No full textThe oxidation of organosulphides catalyzed by hydrogen bonding donors deriving from aminotetrazole has been studied. The oxidation reaction was performed in CH2Cl2 solution using TBHP (1.1 eq.) as a versatile and chemoselective new catalyst to sulfoxides. 5 mol.% catalyst loading afforded organosulfoxides with complete conversion and yields around 90–95%. Tetrazole amide derivatives can be easily recovered by simple filtration and reused several times. Reactions were carried out in scales ranging between mg and multigram in order to test the robustness of the process. 1H-NMR studies and DFT calculations were exploited to disclose the role of tetrazole amide–TBHP complexes in the sulphides oxidation reaction as new performing catalysts
Mo(CO)(6) catalyzed one-pot conversion of allyl aryl ethers to dihydrobenzofurans
No full textMolybdenum hexacarbonyl effectively catalyses a tandem Claisen rearrangement-cyclization reaction of allyl aryl ethers to give good yields of dihydrobenzofurans
Catalytic enantioselective Amadori-Heyns rearrangement of racemic α-hydroxy ketones with arylamines: Synthesis of optically active α-arylamino ketones
No full textA novel synthesis of optically active α-arylamino ketones through an organocatalytic enantioselective Amadori-Heyns rearrangement is described
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