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A new and powerful visible-light-induced difunctionalization of the C-C σ-bond of alkylidenecyclopropanes via a ring-opening process was developed. Importantly, acyl chlorides are used as both acyl and Cl sources. This strategy provides an effective route for the difunctionalization of the C-C bond with an acyl radical and Cl− to construct a new C-C bond and a C-Cl bond in one pot. In addition, it has a wide range of substrates and can tolerate various functional groups.

A method for the preparation of 3-alkylated spiro[4.5]trienones

A simple and efficient method for the regioselective thiolation of p-quinone methides with sodium aryl/alkyl sulfinates has been established using an acid/phosphine-induced radical route under transition-metal-free conditions. A broad range of sodium aryl/alkyl sulfinates and p-quinone methides (p-QMs) are compatible for the reaction, giving the expected products with good to excellent yields. Control experiments were also performed to gain insights into the generation mechanism of thiyl radicals and hydrogen-atom transfer process. This protocol provides a safe and feasible way for the formation of carbon-sulfur bonds.

Heterocyclic compounds, especially oxygen-containing heterocyclic compounds, are crucial moieties in bioactive compounds and drug leads. Substituted chroman-4-ones are a kind of the most significant structural skeletons. Herein, we report a visible-light-induced dual acylation of alkenes for constructing 3-substituted chroman-4-ones, which undergoes a radical tandem cyclization reaction through carbon-carbon bond cleavage of oxime esters by a nitrogen-centered radical strategy. A series of 3-substituted chroman-4-ones were prepared with up to 86% yield.

A simple and efficient method for the silver-catalyzed regioselective phosphorylation of

A convenient and efficient visible-light-induced tandem acylation/cyclization of

A simple and efficient method for the regioselective thiolation of

A novel and convenient visible light-catalyzed tandem radical cyclization of

The effect of acid concentration, time and temperature of modification on the magnesium removal from sepiolite modified by hydrochloric acid, sulfuric acid and nitric acid and on its effectiveness as an active matrix for FCC catalysts, were investigated. The modified sepiolite was characterized by XRD, SEM and N2 adsorption. The results show that the removal of magnesium, specific surface area, and pore specific volume of modified sepiolite are improved with increasing acid concentration, treating time and treating temperature. Hydrochloric acid appears preferable to the modification of sepiolite. The suitable acid modification conditions of sepiolite for FCC catalysts are 80 for 2.5 h with 1 mol L-1 HCl acid, under which the removal of magnesium in sepiolite is 27 %. With the modified sepiolite as an active matrix for FCC catalysts, the specific surface area, pore specific volume and mesopore pore specific volume of the catalysts can increase effectively, the catalysts exhibit excellent heavy-metal resisting performance and better cracking properties as a result of the introduction of magnesium oxide from the modified sepiolite.

In the past decade, ionic liquids have received great attention owing to their potential as green solvent alternatives to conventional organic solvents. In this work, hydrophobic achiral ionic liquids (1-butyl-3-methylimidazolium-hexafluorophosphate([bmim][PF6]), 1-octyl-3methylimidazolium tetrafluoroborate([omim][BF4 ])) were used as solvents in chiral liquid–liquid extraction separation of mandelic acid (MA) enantiomers with β-cyclodextrin (β-CD) derivatives as hydrophilic chiral selectors preferentially forming complexes with (R)-enantiomers. Factors affecting the separation efficiency were optimised, namely the type of the extraction solvents and β-CD derivatives, concentrations of the β-CD derivatives and MA enantiomers, pH, and temperature. Excellent enantioseparation of MA enantiomers was achieved in the ionic liquid aqueous two-phase extraction systems under the optimal conditions of pH 2.5 and temperature of 5 ◦ Cw ith the maximum enantioselectivity (α) of 1.74. The experimental results demonstrated that the ionic liquid aqueous two-phase extraction systems with a β-CD derivative as the chiral selector have a strong chiral recognition ability, which might extend the application of ionic liquids in chiral separation. c 2013 Institute of Chemistry, Slovak Academy of Sciences

The effect of acid concentration, time and temperature of modification on the magnesium removal from sepiolite modified by hydrochloric acid, sulfuric acid and nitric acid and on its effectiveness as an active matrix for FCC catalysts, were investigated. The modified sepiolite was characterized by XRD, SEM and N2 adsorption. The results show that the removal of magnesium, specific surface area, and pore specific volume of modified sepiolite are improved with increasing acid concentration, treating time and treating temperature. Hydrochloric acid appears preferable to the modification of sepiolite. The suitable acid modification conditions of sepiolite for FCC catalysts are 80 for 2.5 h with 1 mol L-1 HCl acid, under which the removal of magnesium in sepiolite is 27 %. With the modified sepiolite as an active matrix for FCC catalysts, the specific surface area, pore specific volume and mesopore pore specific volume of the catalysts can increase effectively, the catalysts exhibit excellent heavy-metal resisting performance and better cracking properties as a result of the introduction of magnesium oxide from the modified sepiolite., U radu je istraživano djelovanje koncentracije kiseline, vremena i temperature modificiranja na uklanjanje magnezija iz sepiolita, kao i na djelotvornost aktivne matrice FCC-katalizatora pripravljenog korištenjem solne, sumporne i dušične kiseline. Modificirani sepiolit je bio karakteriziran rendgenskom difrakcijom praškastih uzoraka, pretražnom elektronskom mikroskopijom te adsorpcijom N2. Dobiveni rezultati ukazuju na povećanje uklanjanja magnezija, specifične površine i volumena pora modificiranog sepiolita s povišenjem koncentracije kiseline, vremena i temperature reakcije. Uvjeti pogodni za kiselinsko modificiranje sepiolita jesu 80 °C tijekom 2,5 sata te c(HCl) = 1,0 mol dm-3, pri čemu se postiže 27-postotno uklanjanje magnezija. Korištenjem modificiranog sepiolita kao aktivne matrice FCC katalizatora, povećana je specifična površina, volumen pora te volumen mezopora katalizatora. Također, tako pripravljeni katalizatori iskazuju odličnu otpornost na kontaminaciju teškim kovinama te bolja krekirajuća svojstva kao posljedicu uklanjanja magnezijeva oksida iz sepiolita.

Volatile oil was extracted from Cuminum cyminum L. by using steam distillation. More than sixty peaks were separated and 49 compounds were identified by gas chromatography-mass spectrometry (GC-MS). The relative amounts of the components were determined by area normalization method. Among the 49 compounds identified, there were 16 hydrocarbons and 32 oxygenated compounds. The main compnents were cuminal and safranal (accounting for 32.26% and 24.46% respectively in the components identified). The other nine compounds with contents all over 1%, were monterpenes, sesquiterpenes, aromatic aldehydes and aromatic oxides etc. The other components with relatively small amounts were chiefly terpenes, terpenols, terpenals, terpenones, terpene esters and aromatic compounds. It is good to separate polar and apolar components in the volatile oil from Cuminum cyminum L. on the GC capillary column of moderate polarity.