Insight into the hard-soft acid-base properties of differently substituted phenylhydrazines in reactions with dimethyl carbonate.

Following the preliminary studies on the reactivity of the ambident nucleophile phenylhydrazine with dimethyl carbonate, investigations involving para-substituted phenylhydrazines were carried out in order to probe differences in the reactivity within this class of nucleophile. Phenylhydrazines substituted by electron withdrawing or donating substituents showed an increase in reactivity of the phenylhydrazine toward dimethyl carbonate. Under the basic conditions used, all phenylhydrazines displayed hard nucleophilicity, signifying that para-substitution on the phenyl ring has little effect on the hard-soft behavior of this class of nucleophile.

Multiphasic heterogeneous catalysis mediated by catalyst-philic liquid phases.

This critical review addresses heterogeneous catalysis in systems where multiple liquid phases coexist and where one of the phases is catalyst-philic. This technique provides built-in catalyst separation, and product recovery for organic reactions. Focus is placed on the components of the multiphasic systems with emphasis on the constituents of the catalyst-philic phases (PEGs, onium salts, ionic liquids) that incorporate the catalysts, as well as on the effects on catalytic efficiency.

Mechanochemical degradation of aromatic sulfonic acids.

Sulfonic acids and sulfonates are widely used as surfactants in various industrial processes. Although partial biodegradation occurs, their release in the environment has determined a widespread pollution problem due to their remarkable tendency towards accumulation. For this reason, various methodologies to effectively degrade sulfonic acids and sulfonates in real matrices are currently under investigation.