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It has been an unproven paradigm that the choice of which ionic liquid to use in a chemical reaction can have a dramatic effect on the outcome of that chemical reaction. We demonstrate, for the first time, that the reaction of toluene and nitric acid in three different ionic liquids gives rise to three completely different products in high yield. Furthermore, ionic liquids can catalyze these reactions with the only byproduct being water.

The NMR and crystallographic characterization of lithium bis[salicylato(2-)]borate, Li(BSB), and lithium bis[1,2-benzenediolato(2-)-O,O‘]borate, Li(BBB), are reported. The single-strand polymer {(MeCN)2 Li(BSB)}∞ crystallizes from a saturated solution of Li(BSB) in ethanenitrile and consists of μ2-{(MeCN)2Li}⁺ cations bridging the exocyclic oxygen atoms of two [BSB]^- anions. Crystallization of Li(BSB) from tetrahydrofuran produces {(THF)2Li(BSB)}∞, which has essentially the same structure as {(MeCN)2Li(BSB)}∞. In contrast, crystals of Li(BBB) grown from THF/diethyl ether or THF/toluene mixtures (1:1) contain adventitious water and form a hydrogen-bonded, three-dimensional lattice comprising {(H2O)2(THF)Li(BBB)} units. This novel structural motif contains the first example of lithium bound to one THF and two water molecules, and also exhibits hydrogen bonding between the water and the THF. Ab initio calculations suggest that the Li−OBBB bond in {(H2O)2(THF)Li(BBB)}∞, while still predominantly ionic in character, is more covalent than an analogous Na−OBBB bond. Crystallization of Li(BBB) from ethanenitrile produces {[(H2O)(MeCN)Li(BBB)]2}∞, which contains the first example of lithium bound to one MeCN and one water molecule. In this case, hydrogen bonding occurs between dimeric {(H2O)(MeCN)Li(BBB)}2 units to form two-dimensional sheets in the ab crystal plane.

Heck coupling of aryl halides or benzoic anhydride with alkenes can be performed with excellent yields in room-temperature ionic liquids, which provide a medium that dissolves the palladium catalyst and allows the product and byproducts to be easily separated. Consequently, the catalyst and ionic liquid can be recycled and reused.

We report the first measurements of the composition and molecular orientation at the surface of a room-temperature ionic liquid&sbd;1-butyl-3-methylimidazolium hexafluorophosphate, [bmim][PF6]. Recoil spectrometry using rare gas ions on continuously refreshed liquid surfaces in vacuo shows that neither ion is significantly enriched in the surface. The average orientation of the cation is with the plane of the ring vertical. The cation ring is rotated about an axis through its center such that the nitrogen atoms and side chains are deeper in the surface with the surface normal passing between the two nitrogen atoms (with an estimated error of ±30°).

Abstract:  Ionic liquids are receiving an upsurge of interest as green solvents; primarily as replacements for conventional media in chemical processes. This review presents an overview of the chemistry that has been developed utilising ionic liquids as either catalyst and/or solvent, with particular emphasis on processes that have been taken beyond the pre-competetive laboratory stage and represent clean industrial technology with significant cost and enviromental benefits.

The alkyltrimethylammonium templates, cited in the original patent for the preparation of MCM-41, have been replaced by a novel set of templates, 1-alkyl-3-methylimidazolium salts. Systematic studies have revealed subtle differences in the performance of the novel templates, and identify them as viable reagents in the synthesis of good quality MCM-41.

Candida antarctica lipase was shown to catalyze alcoholysis, ammoniolysis, and perhydrolysis reactions using the ionic liquids 1-butyl-3-methylimidazolium tetrafluoroborate or hexafluorophosphate as reaction media. Reaction rates were generally comparable with, or better than, those observed in organic media.

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ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

The salts A3(Ru2Br9) with A: Rb, Cs, or 1‐ethyl‐3‐methylimidazolium (emim) are synthesized by a modified literature procedure; usually in low yields typically ranging from 7 to 35%.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Treatment of the metal oxides (I), (III), (V), and (VII) with carbonyl dibromide results in the formation of the metal oxide bromides (II), (IV), (VI), and (VIII).

The kinetics of thermal degradation of the title complexes are studied in dodecahydrotriphenylene solution at ca. 670 K (temp.

The electrochemistry of (IrCl6)2‐and (IrCl6)3‐complexes in the basic title solution has been investigated by means of cyclic and rotating‐disk voltammetry, chronoamperometry, controlled‐potential electrolysis, and transmission spectroelectrochemistry.

The crystal and molecular structures of (Ia), (Ib), and (Ic) (all space group P21/c with Z=4) all contain evidence that the H(4) and H(5) protons of the imidazolium cation enter into hydrogen bonds; the implications of this observation for the interactions in room‐temp.

The synthesis of the title compound (II) occurs either by reduction of the dichloro‐Pt(II) monomer (I) by NaBH4in aqueous EtOH in the presence of two molequiv.

The title compound (III) is prepared by socalled metal‐vapour synthesis.

The title complex salts (I), prepared as shown in the scheme (no yields given), are studied in solution by 1H, 13P, and 195Pt NMR spectroscopy and by conductivity measurements.