Having been inspired by formose-based hypotheses surrounding the origin of life, we report on a novel catalytic route toward a series of recently discovered four-carbon α-hydroxy acids (AHA) and their esters from accessible and renewable glycolaldehyde (GA) in various solvents. The synthesis route follows a cascade type reaction network, and its mechanism with identification of the rate-determining step was investigated with in situ 13 C NMR. The mechanistic understanding led to optimized reaction conditions with higher overall rates of AHA formation by balancing Brønsted and Lewis acid activity, both originating from the tin halide catalyst. An optimal H + /Sn ratio of 3 was identified, and this number was surprisingly irrespective of the Sn oxidation state. Further rate enhancement was accomplished by adding small amounts of water to the reaction mixture, boosting the rate by a factor of 4.5 compared with pure methanol solvent. The cascade reaction selectively yields near 60% methyl-4-methoxy-2-hydroxybutanoate (MMHB). In the optimized rate regime in methanol, an initial TOF of 7.4 mol GA mol Sn −1 h −1 was found. In sterically hindered alcohols (isopropyl alcohol), the rate of AHA formation was even higher, and the corresponding vinyl glycolate esters arose as the main product. Vinyl glycolic acid, 2,4dihydroxybutanoic acid, and its lactone were formed significantly in nonprotic solvent. The corresponding AHAs have serious potential as building blocks in novel biobased polymers with tunable functionality. The incorporation of vinyl glycolic acid in polylactic acid-based polyesters is illustrated, and postmodification at the vinyl side groups indeed allows access to a range of properties, such as tunable hydrophilicity, which is otherwise difficult to attain for pure poly(L-lactic acid).

Ultrasonic irradiation is a promising technique for the degradation of persistent organic molecules such as pharmaceuticals in wastewater. This paper focuses on the sonolytic degradation of ciprofloxacin (CIP), a fluoroquinolone antibiotic. During a first experiment at 25°C and 544 kHz, the degradation of a 15 mg L(-1) CIP-solution showed a pseudo-first order degradation constant k(1) equal to 0.0067 ± 0.0001 min(-1) (n=3). Experiments with the addition of t-butanol as a radical scavenger showed that reaction with *OH radicals is the main degradation route for ciprofloxacin. Since the production of *OH radicals was the highest at 544 kHz, this was also the most favorable frequency for CIP degradation in comparison with 801 (k(1)=0.0055 min(-1)) and 1081 kHz (k(1)=0.0018 min(-1)). The degradation constant is also strongly dependent on the temperature of the bulk solution. The degradation constant increased significantly with increasing temperature from 0.0055 min(-1) at 15°C to 0.0105 min(-1) at 45°C. According to the Arrhenius law, the apparent activation energy was determined to be 17.5 kJ mol(-1). This suggests that the degradation of CIP is diffusion controlled, as is the case for most radical reactions. A Langmuir-type heterogeneous reaction kinetics model could be used to explain the increasing degradation constant with decreasing initial CIP concentration from 0.0204 min(-1) (C(0)=0.15 mg L(-1)) to 0.0009 min(-1) (C(0)=150 mg L(-1)). According to the model a local reaction zone exists at the interface region of the cavitation bubbles. During bubble oscillation, molecules accumulate in the reaction zone and when the bubble finally collapses, the molecules in the reaction zone can be oxidized by the formed *OH radicals. This means that degradation is limited by the available surface at the interface. The model agreed very well with the experimental data (R(2)=0.975). The pseudo rate constant for decomposition (k(d)) was estimated to be 0.40 μM min(-1) and the modeled equilibrium constant (K) was equal to 0.047 μM(-1).

Amphiphilic graft copolymers, based on renewable resources, were synthesized via a "grafting from" strategy. First, a linear hydroxyl functionalized aliphatic polyester, the monomer of which was a fatty acid derivative, was synthesized by a stepwise polymerization. Secondly, trithiocarbonate side groups were attached to the prepared polymer. Finally, a grafting from reversible addition-fragmentation chain transfer (RAFT) polymerization was executed on the macroRAFT agent with the aim to introduce poly(acrylic acid) grafts. The polymers prepared thereof were characterized by nuclear magnetic resonance spectroscopy, size exclusion chromatography and Fourier transform infrared spectroscopy. In order to show the amphiphilic character of those graft copolymers, micelle formation tests were carried out and measured with dynamic light scattering while emulsifying properties were studied via an emulsion stabilization test

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