A process for the hydroformylation of relatively low volatility alkenes (demonstrated for 1-dodecene) in a continuous flow system is described. The catalyst is dissolved in an ionic liquid while the substrate and gaseous reagents are transported into the reactor dissolved in supercritical CO(2), which simultaneously acts as a transport vector for aldehyde products. Decompression of the fluid mixture downstream yields products which are free of both reaction solvent and catalyst. The use of rhodium complexes of triaryl phosphites leads to ligand degradation through reaction of the ionic liquid with water and subsequent attack of the released HF on the phosphite. Sodium salts of sulfonated phosphines are insufficiently soluble in the ionic liquids to obtain acceptable rates, but replacing the sodium by a cation similar to that derived from the ionic liquid, allows good solubility and activity to be obtained. The nature of the ionic liquid is very important in achieving high rates, with 1-alkyl-3-methylimidazolium bis(trifluoromethanesulfonyl)amides giving the best activity if the alkyl chain is at least C(8). Catalyst turnover frequencies as high as 500 h(-1) have been observed, with the better rates at higher substrate flow rates. Rhodium leaching into the product stream can be as low as 0.012 ppm, except at low partial pressures of CO/H(2), when it is significantly higher. Oxygen impurities in the CO(2) feed can lead to oxidation of the phosphine giving higher rates, lower selectivities to the linear aldehyde, increased alkene isomerization and greater leaching of rhodium. However, it is found that under certain process conditions, the supercritical fluid-ionic liquid (SCF-IL) system can be operated continuously for several weeks without any visible sign of catalyst degradation. Comparisons with commercial hydroformylation processes are provided.

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The synthesis of mesoporous silicas in the presence of the dicationic gemini surfactant [CH 3 (CH 2 ) 15 N(CH 3 ) 2 (CH 2 ) 3 N(CH 3 ) 3 ]Br 2 (C16-3-1) has been investigated at low temperatures (24 uC) under basic and acidic conditions. Under basic conditions, the SBA-2 phase (based on a close-packed arrangement of micelles and exhibiting frequent stacking faults) is observed, with hollow sphere morphology. Under strongly acidic conditions, the phase SBA-1 (Pm3 ¯n) and the SBA-2 family of phases (based on the close packing of micelles) are observed, depending on the surfactant and silicate content of the original gel. Conditions under which the pure hexagonally close-packed end member of the family (P6 3 /mmc) is formed have been identified. SBA-1 and the pure hexagonally close-packed end member are prepared with well-defined morphologies. The adsorption of nitrogen and the hydrocarbons cyclopentane and mesitylene reveal that SBA-2 prepared in basic media has a cage structure where the cages are linked through small (v4 A ˚) micropores, whereas the silicas prepared in acidic media have larger pores after calcination. SBA-1 and a poorly ordered SBA-2, prepared using C16-3-1 under acidic conditions, are able to adsorb mesitylene (diameter ca. 8 A ˚), whereas the hexagonal end member of the SBA-2 series prepared under acidic conditions is able to adsorb cyclopentane (diameter ca. 5 A ˚) but not mesitylene.

Lactic acid oligomers were prepared using sodium and potassium hydroxyacids as initiators for lactide polymerization leading to the formation of surface active molecules in a one-pot synthesis, requiring no additional catalysts or volatile organic solvents. The initiator systems that were investigated included sodium and potassium salts of lactate, mandelate, γ-hydroxybutyrate, α-hydroxybutanoate, α-hydroxyhexanoate, α-hydroxyoctanoate, α-hydroxyisovalerate, and 2,2-bis(hydroxymethyl)butyrate. Poly(lactic acid) oligomers were successfully isolated from polymerizations initiated by all species listed using the catalyst-free synthetic route employed. The molecular weights of the oligomeric species ranged from 800 to 2400 Da (measured against poly(styrene) standards), and polydispersities were all below 1.5. All isolated polymers showed surfactant activity with low CMC values and a high propensity for aggregation that increases as molecular weight increases. Additionally, producing an A−B−A type polymeric structure, where the B block is defined as a moiety containing a single functional group, was shown to give improved application performance compared with the equivalent A−B type structure.