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A switchable hydrophilicity solvent (SHS) was studied for its effectiveness at extracting lipids from freeze-dried samples of Botryococcus braunii microalgae. The SHS N , N -dimethylcyclohexylamine extracted up to 22 wt.% crude lipid relative to the freeze-dried cell weight. The solvent was removed from the extract with water saturated with carbon dioxide at atmospheric pressure and recovered from the water upon de-carbonation of the mixture. Liquid chromatography–mass spectrometry (LC–MS) showed that the extracted lipids contained high concentrations of long chain tri-, di- and mono-acylglycerols, no phospholipids, and only 4–8% of residual solvent. Unlike extractions with conventional organic solvents, this new method requires neither distillation nor the use of volatile, flammable or chlorinated organic solvents.

The catalytic utility of [κ2-{3-iPr2P-2-O-indene}Rh(COD)] (COD = η4−1,5-cyclooctadiene) 1a in the hydroformylation of styrenes was examined. Complex 1a was shown to be an effective pre-catalyst in benzene and tetrahydrofuran, exhibiting good conversions to aldehyde and high branched-to-linear selectivity for styrene, 4-chlorostyrene, and 4-methylstyrene under reasonably mild conditions (1000 psi syngas; 1.8 mol% Rh, 45 °C, 2–5 h). Under analogous conditions, the iridium congener of 1a proved inactive for hydroformylation. The synthesis and crystallographic characterization of the new complex [κ2-{2-iPr2PC6H4O}Rh(COD)] 2 is also reported; the catalytic performance of 2 in the hydroformylation of styrene was found to be comparable to that of 1a under similar catalytic conditions.

The switchable polarity solvent (SPS) of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) and an alcohol (e.g. 1-propanol) reversibly switches to a higher polarity ionic liquid, [DBUH(+)][RCO3(-)], when treated with CO2. A long-lived species with unique properties was detected in an investigation into the use of SPS to control the lifetime of the merocyanine (MC) form in a spiropyran (SP)-MC molecular photoswitch. Irradiation of SP in 1-propanol (PrOH) in the presence of DBU generates a new species (λmax = 420 nm). This species converts to MC upon bubbling with CO2, which produces [DBUH(+)][PrOCOO(-)]. It is proposed that a mixture of 1,2 and 1,4 alkoxide addition products form as a result of nucleophilic attack on the conjugated diene system of MC, where alkoxide formation arises from equilibration of highly basic DBU and the alcohol. These adducts revert to MC upon application of CO2 or addition of acid. Determination of the overall equilibrium constant for alkoxide adduct formation involving DBU was afforded through Benesi-Hildebrand analysis.

Several tertiary amines serve as switchable-hydrophilicity solvents, meaning that they are hydrophobic solvents having very low miscibility with water when under air but hydrophilic solvents having complete miscibility with water when under an atmosphere of CO2. Unlike the only previously reported switchable-hydrophilicity solvent, these amines are easily prepared and, in some cases, commercially available. The effect of temperature, gas flow rates, choice of amine and additives on the switching process is described. These solvents can be applied to the recycling of polystyrene foam.

The syntheses, characterisation and biological activities (IC50; DNA binding) of four mononuclear Pt oxazoline complexes are reported. These materials are the compounds cis-[PtCl2(NH3)(Etox-κ1N)] (1: Etox = 2-ethyl-2-oxazoline), [PtCl2(anilox-κ2N,N′)] (2: anilox = 4,4-dimethyl-2-[o-anilinyl]-2-oxazoline), cis-[PtCl2(Etox-κ1N)2] (3) and [PtCl(pyox-κ3N,N′,N′)] (4: pyoxH = pyridine-2-carboxyanil-[o-{4,4-dimethyl-2-oxazolinyl}-ide]) and all four are shown to have slightly lower cytotoxicities in vitro when compared to cisplatin against the A2780 ovarian cancer cell line. These new materials all appear to be bio-active via the formation of DNA adducts. Complexes 1 and 2 have been further characterised in the solid-state by X-ray diffraction methods.