Poly(ionic liquid) superabsorbent for polar organic solvents.

A simple, polymerized ionic liquid (poly(IL)) based on methylimidazolium cations tethered to a polystyrene backbone exhibits superabsorbent behavior toward polar organic solvents, most notably propylene carbonate (PC) and dimethyl sulfoxide (DMSO), wherein the poly(IL) was observed to swell more than 390 and 200 times (w/w) its original mass, yet absorbs negligible quantities of water, hexanes, and other solvents, many of which were miscible with the IL monomer. Although solubility parameters and dielectric constants are typically used to rationalize such behaviors, we find that poly(IL)-solvent compatibility is most clearly correlated to solvent dipole moment. Poly(IL) superabsorbency is not reliant upon the addition of a cross-linking agent.

Synthesis of the purported ent-pochonin J structure featuring a stereoselective oxocarbenium allylation.

The synthesis of the alleged natural product pochonin J is presented. Key steps of this convergent synthesis include a chemoselective Wacker oxidation, and an Evans' anti-reduction of the resulting ketone. Upon ozonolysis, this intermediate undergoes a 6-exo-trig cyclization to give a hemiketal intermediate, the key oxocarbenium precursor.