The specific ionic conductivity, dynamic viscosity, and electrochemical stability of several imidazolium salts are reported as neationic liquids their solutions in organic solvents. temperature dependence conductivity viscosity analyzed for 1‐ethyl‐3‐methylimidazolium 1,2‐dimethyl‐3‐n‐propylimidazolium salts, the influence theanions bis(trifluoromethylsulfonyl)imide , bis(perfluoroethylsulfonyl)imide hexafluoroarsenate hexafluorophosphate tetrafluoroborate on these properties discussed....

ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXTChiral Porous Solids Based on Lamellar Lanthanide PhosphonatesOwen R. Evans, Helen L. Ngo, and Wenbin LinView Author Information Department of Chemistry, CB #3290 University North Carolina Chapel Hill, 27599 Cite this: J. Am. Chem. Soc. 2001, 123, 42, 10395–10396Publication Date (Web):September 28, 2001Publication History Received8 June 2001Published online28 September inissue 1 October...

Abstract For see ChemInform in Full Text.

A chiral two-dimensional network is the basis for structure of a homochiral solid exploiting metal–carboxylate coordination. The synthesis involved enantiopure bridging ligands and metal–organic secondary building units (SBUs), resulted in ethoxy-protected BINOL functionalities pointing into cavities this crystalline zeolitic material (see picture). Supporting information article available on WWW under http://www.angewandte.com or from author. Please note: publisher not responsible content...

While radiologists can describe a fracture's morphology and complexity with ease, the translation into classification systems such as Arbeitsgemeinschaft Osteosynthesefragen (AO) Fracture Dislocation Classification Compendium is more challenging. We tested performance of generic chatbots aware specific knowledge AO provided by vector-index compared it to human readers. In 100 radiological reports we created based on random codes, codes significantly faster than humans (mean 3.2 s per case...

Catalytic building blocks: Chiral porous zirconium phosphonates containing Ru-binap moieties are synthesized by a molecular building-block approach, and characterized variety of techniques. These hybrid solids used for enantioselective heterogeneous asymmetric hydrogenation β-keto esters with ee values up to 95 % (see picture). Ready tunability such approach promises lead useful catalysts. Supporting information this article is available on the WWW under...

A new chiral bridging ligand, 2,2'-pentaethylene glycol-1,1'-binaphthyl-6,6'-bis(phosphonic acid), was synthesized in 40.7% overall yield five steps and used to generate single crystals of the first porous lanthanide phosphonates with crown ether pillars. Single-crystal powder X-ray crystallography established that these decorated lamellar solids retain their framework structures after removal included guest molecules serve as structural models for are exploitable bulk separations.

A family of chiral diphosphanes with systematically tunable electronic and steric properties have been used in the asymmetric hydrogenation β-aryl ketoesters excellent ee values (up to 99.8 %) by taking advantage remarkable 4,4′-substituent effects on binap. These highly enantioselective Ru catalysts also effectively immobilized room-temperature ionic liquids (RTIL). Supporting information for this article is available WWW under http://www.wiley-vch.de/contents/jc_2002/2004/z53415_s.pdf or...

A homochiral triple helix was self-assembled from an axially chiral bipyridine and a linear metal-connecting point, which further assembles into 2D network via infinite π⋯π stacking interactions acts as host for the inclusion of guest molecules.

Abstract The self‐metathesis of readily available monounsaturated FA has the potential being an important pathway for synthesis symmetrical long‐chain unsaturated‐α,ω‐dicarboxylic acids (C 18 −C 26 ). Previous studies on esters using ruthenium catalysts in solution, however, suffered from low conversions as a result thermodynamic control reaction. We have found that second‐generation Grubbs catalyst can effectively catalyze solvent‐free varying purity (from 90 to 99%) afford two...

The reactions of 2,2′-dimethoxy-1,1′-binaphthyl-3,3′-bis(4-vinylpyridine) (L) with AgNO3 or AgClO4 at 70 °C gave rise to two novel luminescent homochiral lamellar coordination polymers, AgL2X (X = NO3− for 1 ClO4− 2), which are built from linking helical chains by Ag(I) atoms as hinges.

Biodiesel (BD) is an alternative diesel fuel derived from both vegetable oils and animal fats. Currently, most BD made by alkali-catalyzed transesterification of a refined oil or fat, the cost which major expenditure in producing BD. Yellow brown greases are readily available renewable fats that less expensive hence represent attractive feedstocks for production The high free fatty acid (FFA) content these feedstocks, however, makes it difficult to produce using base-catalyzed...

Abstract Branched‐chain (bc) saturated fatty acids (SFA) have potential as oleochemical intermediates since they better oxidative stability than linear unsaturated (UFA) and low‐temperature properties SFA. Previous studies in converting UFA to bc‐FA using clay catalysts resulted only modest yields conversions. Recent reports, however, suggested that certain zeolites can be effective for higher In this work, we examined the scope of zeolite‐catalyzed synthesis starting from readily available...

We successfully optimized an analytical method using gel permeation chromatography followed by direct sample introduction comprehensive two-dimensional gas with time-of-flight mass spectrometry to quantify multiple groups of targeted persistent organic pollutants and halogenated natural products (HNPs) simultaneously in fish oil samples. This new has a wider scope than the traditional approach use methods cover each class compounds. Our analysis revealed that relatively more volatile lighter...

Most analytical methods for persistent organic pollutants (POPs) focus on individual groups of targeted analytes. Therefore, analysis multiple classes POPs typically entails several sample preparations, fractionations, and injections, whereas other chemicals possible interest are neglected or lost. To analyze a wider scope contaminants in fish oil, we developed an approach to combine the untargeted using automated direct introduction (DSI) comprehensive two-dimensional gas chromatography...

Abstract Saturated branched‐chain fatty acids (sbc‐FAs) are found as minor constituents in several natural fats and oils. Sbc‐FAs of interest since they have lower melting points than their linear counterparts exhibit good oxidative stability; properties that make them ideally suited a number applications. We (and others) previously synthesized sbc‐FAs by clay‐ or zeolite‐catalyzed isomerization unsaturated linear‐chain (ulc‐FAs) to (ubc‐FAs) were subsequently hydrogenated the desired...

Abstract The development of viable technologies for producing green products from renewable fats and oils is highly desirable since such materials can serve as replacements non‐renewable poorly biodegradable petroleum‐based products. Mixtures saturated branched‐chain fatty acid isomers (sbc‐FAs), commonly referred to isostearic acid, are important intermediates the production lubricants, cosmetics, emollients, hydraulic fluids. Present methods sbc‐FAs, however, often give low yields sbc‐FAs...

Polar phosphonic acid-derived Ru-BINAP systems were used to catalyze asymmetric hydrogenation of beta-keto esters in room temperature ionic liquids (RTILs) with complete conversions and ee values higher than those obtained from homogeneous reactions MeOH (up 99.3%), recycled by simple extraction for four times without the loss activity enantioselectivity.

A family of tunable precatalysts Ru(4,4'-BINAP)(chiral diamine)Cl2 was synthesized and used for highly enantioselective hydrogenation aromatic ketones. This result differs from previous chiral diphosphines that rely on the bis(xylyl)phosphino groups to control enantioselectivity. An X-ray structural study reveals bulky substituents 4,4'-positions BINAP can effectively create a suitable pocket in transition state thus provide new mechanism enantiocontrol such remarkable asymmetric catalytic process.

Homochiral 3D metal-organic open frameworks based on enantiopure atropisomeric dicarboxylic acid bridging ligands and dilanthanide secondary building units exhibit an unprecedented 4(9)6(6) topology, possess ethoxy-protected BINOL functionalities that are pointing toward the channels.

[structure: see text] A recently developed BINAP derivative with trimethylsilyl substituents on the 4- and 4'-positions of binaphthyl skeleton, 2,2'-bis(diphenylphosphino)-4,4'-bis(trimethylsilyl)-1,1'-binaphthyl (tms-BINAP), was used in a variety transition-metal-catalyzed asymmetric carbon-carbon bond-forming reactions. In pi-allylpalladium-mediated reactions, tms-BINAP gave better enantioselectivity than unsubstituted BINAP, origin improved gained from an X-ray structural study...