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Abstract: The asymmetric transfer hydrogenation of nonfunctionalized aromatic ketones catalyzed by Ru-TsDPEN was performed successfully in a mixture of poly(ethylene glycol) (PEG) and water. High activity and enantioselectivity were obtained, which were better than or comparable to those obtained in conventional organic solvents. The unmodified catalyst could be easily recovered after extraction of the reduced product with a less polar solvent such as hexane, and was reused at least 14 times without obvious loss in enantioselectivity. These results indicate that the inexpensive and non-toxic aqueous PEG can serve as a new means for the immobilization of Ru-TsDPEN catalyst and related variants without calling for catalyst modification. [Copyright &y& Elsevier]

Abstract: The Michael addition of thiols to p-quinones proceeds efficiently in water at room temperature without a catalyst. Significant rate acceleration of this reaction is observed in water compared to organic solvents. Water played a dual role in simultaneously activating the quinones and thiols. This new methodology constitutes an easy, highly efficient and green synthesis of diaryl sulfides and aryl alkyl sulfides. [Copyright &y& Elsevier]

Abstract: The Heck arylation of 2-methylprop-2-en-1-ol in ionic liquids and organic solvents is reported using a range of homogeneous and heterogeneous palladium catalysts. Higher activity is observed in the ionic liquid media compared with N-methylpyrrolidinone and under solventless conditions. The ionic liquid-catalyst system may be recycled easily with little loss in activity, although significant palladium leaching from the heterogeneous catalyst was observed. In the case of trans-bis(2,3-dihydro-3-methylbenzothiazole-2-ylidene)diiodopalladium(II) reported to be highly active for this transformation, significant induction periods were observed indicating that nanoparticles may be responsible for the catalysis. Using the ionic liquid Heck reaction, a recyclable synthesis for the fragrance β-Lilial® has been developed. [Copyright &y& Elsevier]