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[reaction: see text] In sharp contrast to their isopropyl counterparts, a variety of (Z)-isopropenyl tertiary bicyclo[2.2.2]octenols undergo facile anionic oxy-Cope rearrangements allowing the stereoselective incorporation of an isopropenyl group into polycyclic skeletons such as the tricyclic system of vinigrol, bicyclo[5.3.1]undecane, and cis-decalin frameworks. This rate acceleration is probably due to the stabilization of the transition state by the additional unsaturation on the terminal position.

International audienceThe present work aimed to investigate the removal feasibility of organic micropollutants (o-nitrophenol (o-NP) and p-nitrotoluene (p-NT)) from aqueous solutions using an original activated carbon prepared from chicken bones (CAB). The activated carbon is treated with 30% H2O2 and carbonised at 800 degrees C for 3h. Thus, the obtained CAB is characterised by the way of different physico-analytical methods as X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy and the method of Boehm titration. The kinetic experimental data were fitted according to theoretical models: pseudo-first-order, pseudo-second-order, intraparticle diffusion models and the Elovich and Avrami models. The maximum removal obtained for o-NP and p-NT is around similar to 80% at 5-20mg/L respectively. The required time for the adsorption equilibrium is between 70 and 145min. The adsorption kinetics of o-NP and p-NT is tested according to the intraparticle diffusion equations. The results obtained in the present study indicate that the bioadsorbent material CAB is a promising adsorbent for the removal of organic micropollutants from wastewater

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Terpenes Terpenes U 0200Rate Acceleration of Anionic Oxy-Cope Rearrangements Induced by an Additional Unsaturation. -A facile anionic oxy-Cope rearrangement of (Z)-isopropenyl tertiary bicyclooctenols allowing the stereoselective incorporation of an isopropyl group into polycyclic skeletons such as the tricyclic system of vinigrol, bicycloundecane and cis-decalin frameworks is reported. In contrast to these results, attempts on the rearrangement of the corresponding isopropyl counterparts fail. This effect is explained in terms of stabilization of the transition state by the additional vinyl group. -(GENTRIC, L.; HANNA*, I.; HUBOUX, A.; ZAGHDOUDI, R.; Org. Lett. 5 (2003) 20, 3631-3634; Lab. Synth. Org., CNRS, DCSO, Ec. Polytech., F-91128 Palaiseau, Fr.; Eng.) -Bartels 06-143