cis-3-Acetoxy-4-(3-aryloxiran-2-yl)azetidin-2-ones were prepared through a Staudinger [2+2]-cyclocondensation between acetoxyketene and the appropriate epoxyimines in a highly diastereoselective way. Subsequent potassium carbonate-mediated acetate hydrolysis, followed by intramolecular ring closure through epoxide ring opening, afforded stereodefined 3-aryl-4-hydroxy-2-oxa-6-azabicyclo[3.2.0]he...

BACKGROUND Continuous dialysis could provide benefit by constant removal of potassium and phosphate. This study investigates the suitability of specific potassium and phosphate sorbents for incorporation in an extracorporeal device by capacity and regenerability testing. METHODS Capacity testing was performed in uraemic plasma. Regenerability was tested for potassium sorbents, with adsorption...

Materials. Ethylbromoacetate (97%), potassium carbonate (99%), diethyl ether (99.8%), ethylenediamine (99%), dichloromethane (99.6%), sodium triacetoxyborohydride (97%), sodium borohydride (98%), propionaldehyde (97%), poly(ethylene glycol) methyl ether thiol (PEG-SH, average mw 2000), formic acid (96%), formaldehyde (37% wt in H2O), sodium hydroxide(97%), propionaldehyde (97%), trifluoroacetic...

Heck reaction catalyzed by cobalt hollow nanospheres has been developed; the coupling of alkenes with aryl iodide or aryl bromide in the presence of potassium carbonate provides the corresponding products with moderate to good yields, which reveals obvious advantages such as low-cost catalyst, ligand-free condition, the recyclability of the catalyst and simple experimental operation.

The present study reports the reaction of 4-bromomethylcoumarins with salicylidineaniline in acetone with two equivalents of potassium carbonate resulted in the formation of title compounds at room temperature via intramolecular aldolization. The obtained compound is thermodynamically and kinetically stable with highly stereoselective and excellent yield.

The title compound, C(11)H(13)ClO(3), has been obtained in the reaction of 2, 4-dihydroxy-lacetonephenone, potassium carbonate and 1-bromo-3-chloro-hexane. The hydr-oxy group is involved in an intra-molecular O-H⋯O hydrogen bond. The crystal packing exhibits no significantly short inter-molecular contacts.

The aza-Henry reaction of chiral fluoroalkyl α,β-unsaturated N-tert-butanesulfinyl ketoimines and nitromethane was achieved in the presence of 0.2 equivalent of anhydrous potassium carbonate to give the corresponding adducts diastereoselectively in high yields. Transformations which highlighted the synthetic potential of these aza-Henry adducts were also performed.

The title compound, C(15)H(14)O(3), has been obtained from the reaction of 2,4-dihy-droxy-acetophenone, potassium carbonate and benzyl bromide. The remaining hy-droxy group is involved in an intra-molecular O-H⋯O hydrogen bond. In the crystal, inter-molecular C-H⋯O contacts occur.

The 1,4-addition of a monofluoromethyl nucleophile to a variety of alpha,beta-unsaturated compounds has been achieved under mild conditions using either phosphines or potassium carbonate at room temperature. alpha-Substituted fluoro(phenylsulfonyl)methane easily undergoes Michael addition to alpha,beta-unsaturated ketones, esters, nitriles, sulfones, as well as propynoates at room temperature t...