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Graphical abstract The synthesis of polyureas from CO 2 and diamines with K 3 PO 4 as the catalyst. Highlights • A simple and efficient K 3 PO 4 catalyst to realize the CO 2 activation. • The direct synthesis polyureas from CO 2 and diamines. • The catalytic performance is essentially consistent with the basicity of salts. Abstract A series of potassium alkali salts (K 3 PO 4 , K 2 HPO 4 , KH 2 PO 4 , K 2 CO 3 , KHCO 3) were applied in CO 2 conversion to polyureas. It was observed that the catalytic activity was related to the alkalinity of salts and solvents. K 3 PO 4 was found to be a highly active catalyst for the polymerization of CO 2 , and various polyureas were achieved from inferior to superior yields. Characterization of spent catalyst by IR and XRD demonstrated that the K 3 PO 4 was completely transformed into less active K 2 HPO 4 , KH 2 PO 4 and KHCO 3 via reaction with CO 2 and water during the polymerization process. The products were examined by IR, 13C NMR, TGA and DSC, indicating that the product obtained from CO 2 possesses the ureas structure and good thermal stability. [ABSTRACT FROM AUTHOR]

Currently, industrial production of isocyanates, or diisocyanates in particular, has been exclusively based on phosgene processes. Phosgene is extremely toxic and large amounts of corrosive HCl are produced as a side product. In the view of environment protection and society safety, development of non-phosgene processes for isocyanates production will be highly desired, and this should be one of the most important missions for green chemistry and catalysis. In this review, efforts for development of non-phosgene method for syntheses of isocyanates, i.e., catalytic syntheses of N-substituted carbamates from nitro- or amino-compounds with CO, dimethyl carbonate ( DMC), urea and even CO2 etc. as carbonyl sources, then thermal cracking of N-substituted carbamates to afford corresponding isocyanates, are summarized, and a brief prospect for non-phosgene syntheses of isocyanates is also addressed. [ABSTRACT FROM AUTHOR]

Brønsted acidic ionic liquids as efficient and reusable catalysts for the protection of alcohols as tetrahydropyranyl (THP) ethers under solvent-free conditions at room temperature was investigated. Good to excellent yields were obtained at a faster rate over [BMIm][HSO 4 ] or [BMIm][H 2 PO 4 ]. [ABSTRACT FROM AUTHOR]

Here, we show the one-step synthesis of N-alkylated anilines from nitrobenzenes and alcohols catalyzed by nano-gold catalyst. The yields to N-alkylated anilines were ∼90% under mild conditions. The mechanism of this reaction was explored. It shows promise for clean and simple synthesis of N-alkylated anilines. [ABSTRACT FROM AUTHOR]

A novel selective one-pot synthesis of unsymmetric tertiary amines catalyzed by a simple hydrothermally formed Cu/Al oxide catalyst is introduced. [ABSTRACT FROM AUTHOR]

SO3H-functionalized ionic liquids have been employed as an alternative reaction medium to conventional acid catalysts for oligomerization of various olefins, to produce branched olefin derivatives in high conversions and excellent selectivity. The ionic liquid plays a dual role as both catalyst and solvent, providing an efficient and reusable acidic catalyst system for the oligomerization of olefins. [Copyright &y& Elsevier]

A diagram is presented which shows the structure of light-promoted N,N-dimethylation of amine and nitro compound with methanol catalyzed by palladium/titanium dioxide (Pd/TiO2 at room temperature.

The Pd/NiO catalyst exhibits excellent activity and selectivity in the reductive amination reaction using a wide range of amines and aldehydes as substrates. [ABSTRACT FROM AUTHOR]

Phenol (I) and benzene (III) derivatives with various structures are hydrogenated into the corresponding cyclohexanol (II) and cyclohexane derivatives (IV) with good to excellent yields. [ABSTRACT FROM AUTHOR]

The article presents chemical equations related to the article "Amine Formylation via Carbon Dioxide Recycling Catalyzed by a Simple and Efficient Heterogeneous Palladium Catalyst" by X. Cui and others, published in the periodical "Chemical Communications" in 2014.

The title catalyst exhibits high activity and excellent chemoselectivity in the reduction of nitro substituted arenes to the corresponding anilines. [ABSTRACT FROM AUTHOR]

The article focuses on the development of a non-noble metal catalyst for amination of alcohols accompanied with ammonia and amines.

Abstract: Three new protic ionic liquids based on 2-methylpyridinium were prepared and characterized. Their catalytic activities for the tert-butylation of phenol and the esterification of cyclic olefins with acetic acid were examined and satisfactory results were obtained over 2-methylpyridinium trifluoromethanesulfonate ([2-MPyH]OTf). Hammett method was used to determine the acidity order of these ionic liquids and the results are consistent with the catalytic activities observed in the acid-catalyzed probe reactions. [Copyright &y& Elsevier]

Abstract: The carbonylation of amines with propargylic alcohol using CO2 as carbonyl source to yield N-substituted 4-methylene-2-oxazolidinones could efficiently proceed in ionic liquids, and various 4-methylene oxazolidinones with high yields could be obtained under relatively mild conditions. This result showed that ionic liquid might be an effective catalyst and reaction medium for the activation of CO2, which also offered a new way to the chemical fixation of CO2. [Copyright &y& Elsevier]

After modifications of rare earth and phosphorus, the acidity density and the strength in the pores of zeolite Y (PREUSY) are improved effectively; the surface acidity is suitably reduced and weakened owing to the interaction of rare earth cation and phosphate anion. NH3-TPD analysis showed that the acid distribution of the modified zeolite is more concentrated on the range of intermediate and strong acidity. This kind of modification can direct more hydrocarbons to enter into the pores to be converted and remarkably reduces the possibility of naphtha olefins forming through a surface cracking reaction. In addition, because naphtha olefin reduction does not completely depend on olefin saturation through secondary hydrogen transfer reaction, this kind of reaction mode can decrease the excessive cracking of mediate distillate and can improve the diesel oil yield (LCO) effectively. Some reaction pathways were proposed. [Copyright &y& Elsevier]

Several acid-functional ionic liquids were physically confined into the silica gel through a sol–gel process and used as effective catalysts for deoximation reactions, which proceeded under ambient temperatures without addition of any co-catalysts or oxidizing and reducing agents. [Copyright &y& Elsevier]

An efficient route for the synthesis of hydroxy carbamates via reaction of epoxides with amines and CO2 is developed. [ABSTRACT FROM AUTHOR]

TiO2-Cr2O3/SiO2 catalyzes the synthesis of N-substituted carbamates using urea as carbonyl source. [ABSTRACT FROM AUTHOR]

The article presents information on methylation of Amines, Aromatic Nitriles and Nitrobenzenes with Carbon Dioxide and molecular Hydrogen.