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We report a new continuous method for forming ethers, acetals and ketals using solid acid catalysts, DELOXAN ASP or AMBERLYST 15, and supercritical fluid solvents. In the case of ether formation, we observe a high selectivity for linear alkyl ethers with little rearrangement to give branched ethers. Such rearrangement is common in conventional syntheses. Our approach is effective for a range of n-alcohols up to n-octanol and also for the secondary alcohol 2-propanol. In the reaction of phenol with an alkylating agent, the continuous reaction can be tuned to give preferential O- or C-alkylation with up to 49% O-alkylation with supercritical propene. We also investigate the synthesis of a range of cyclic ethers and show an improved method for the synthesis of THF from 1,4-butandiol under very mild conditions.

Continuous hydrogenation in supercritical fluids has been shown to be a technically viable alternative to traditional batch-wise methodologies. Clearly, the next stage of development of this technology is the application of immobilised enantioselective catalysis in the preparation of optically active products. Enantioselective hydrogenation has been successfully carried out in supercritical carbon dioxide using batchtype reactors but has yet to be efficiently carried out continuously. Here we examine an established method of catalyst immobilisation and demonstrate its suitability for application in continuous reactors using supercritical carbon dioxide as solvent.

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Continuous flow supercritical carbon dioxide (scCO 2 ) has previously been shown (P. Stephenson, P. Licence, S. K. Ross, M. Poliakoff, Green Chem. 2004, 6, 521) to be a viable medium for conducting continuous asymmetric hydrogenation when it is combined with an appropriate enantioselective catalyst. Here we examine the use of a composite catalyst immobilisation system modified with several different types of asymmetric bisphosphine ligands in continuous flow scCO 2 . In particular, proprietary ligands from Solvias AG were found to be the most successful, with Josiphos 001 improving the enantiomeric excess (ee) to> 80 % in the asymmetric hydrogenation of dimethyl itaconate (DMIT); this ee is higher than that reported for the batch hydrogenation of DMIT using a homogeneous catalyst fully dissolved in scCO 2 (S. Lange, A. Brinkmann, P. Trautner, K. Woelk, J. Bargon, W. Leitner, Chirality 2000, 12, 450).

This study investigated motherϪinfant interactions in lowland gorillas (Gorilla gorilla gorilla) with particular focus on the relative role of mothers and infants in creating situations that are potentially conducive to infant social learning. Eleven gorilla motherϪinfant dyads were focally observed in weekly 1-hr sessions for 12 months. Spatial relationships were affected by age as well as by ambient temperature. Although the youngest infant was encouraged by its mother to walk and climb, mothers showed little or no encouragement in other contexts. In contrast, infants were quite interested in their mothers' activities, on some occasions repeated their mother's behavior, and actively encouraged their mothers to share food, play, or follow them. These findings suggest that gorilla infants are more active than their mothers in creating situations that are potentially conducive to the acquisition of knowledge or skills.Over the last 3 decades, the study of motherϪinfant relationships in primates has concentrated on understanding the proximate determinants and adaptive function of interindividual differences in maternal behavior, with particular emphasis on the regulation of contact and proximity between mother and infant (Fairbanks, 1996). Most of this research has been conducted with Old World monkeys, notably macaques, baboons, and vervet monkeys, because of the ease with which large populations of these primates can be studied for long periods of time. Recently, a growing interest in primate communication and cognition has stimulated attention to the exchange of signals and the transmission of information between mothers and infants through social learning pro-