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Abstract: Novel and efficient organic catalysts of quaternary onium tribromide and the related metal-containing catalysts of SalenCoX/PTAT were developed to catalyze the coupling reaction of carbon dioxide and epoxides generating relevant cyclic carbonates including chiral propylene carbonate under extremely mild condition. [Copyright &y& Elsevier]

Abstract: Novel and high efficient catalysts of metal porphyrin (M(TPP)X, M=Co, Fe, Ru, Mn; X=Cl−, Br−, OAc−, OTs−, Cl3CCO2 −)/phenyltrimethylammonium tribromide (PTAT) were developed to catalyze the coupling reaction of carbon dioxide and epoxides at room temperature. [Copyright &y& Elsevier]

Abstract: A series of titanium complexes of the general formula [N-(3,5-di-tert-butylsalicylidene)-2-alkyl-sulfanylanilinato]Ti(IV)Cl3 (5a, b, e and f) exhibited very high catalytic activities in ethylene homo- and copolymerization with various α-olefins in the presence of modified methylaluminoxane (MMAO). The results showed that steric hindrance of the alkylthio groups in 5a–f strongly influenced the polymerization behavior. An increase in the steric hindrance of these alkyl units led to the decrease in both catalytic activity and comonomer incorporation ratio. On the other hand, the amount of α-olefin incorporated into the copolymer chain depended on the molar ratio of the monomers in the polymerization reaction and was slightly influenced by the chain length of α-olefin. Comparisons between alkylthio and arylthio substituents on catalyst performance were also discussed in this article. [Copyright &y& Elsevier]

Abstract: Several phenyl ethers were prepared under solvent-free condition at room temperature with good to excellent yields by simply grinding the mixture of relevant phenol, alkyl bromide, anhydrous potassium carbonate and organic base as catalyst in a mortar. This method is easy to handle and provides also a convenient procedure for protecting phenols in organic synthesis. [Copyright &y& Elsevier]