Single-crystal X-ray analysis of the 5'-bromo-l',3'-xyly~-l8-crown-5* tert-butylammonium hexafluorophosphate complex shows that the complex is of the "nesting" type in which the cation and the aryl group are on the same face of the macroring and that the macroring has a (ag'a)(ag-a)lag'a)(ag-a)(ag'a)lag-a) eonformation. Among crown ethers with aryl-sub-units, 1' ,3'-xylyl crown ethers (1) have ...

Radiolabeled cholesteryl ethers are widely used as non-metabolizable tracers for lipoproteins and lipid emulsions in a variety of in vitro and in vivo experiments. Since cholesteryl ethers do not leave cells after uptake and are not hydrolyzed by mammalian cellular enzymes, these compounds can act as markers for cumulative cell uptakes of labeled particles. We have employed [3H]cholesteryl oleo...

structurally different trimethyl silyl ethers are oxidized with bu4/nio4 in the presence of alcl3 and bf3 as catalysts in ch3cn and chcl3 under reflux conditions. the corresponding carbonyl compounds are isolated in good yields.

Antimitotic natural products that bind to cellular microtubules can be used as anticancer agents, and we are studying the cellular mechanisms of these compounds.1 The fungal metabolite phomopsin A is a key structure in these studies, and we are currently pursuing its synthesis.2 Our retrosynthetic analysis of phomopsin A targeted the chiral tertiary alkyl-aryl ether as a key disconnection withi...

Treatment of thiol ester with bis(iodozincio)alkane in the presence of palladium catalyst followed by silylation affords Z-silyl enol ether chemo-, regio- and stereoselectively.

A concise asymmetric total synthesis of (þ)-indatraline from readily available cinnamic acid is described. The key steps include Corey’s oxazaborolidine-catalyzed asymmetric carbonyl reduction and a highly stereoselective amination of chiral benzylic ether with retention of stereochemistry using chlorosulfonyl isocyanate. 2013 Elsevier Ltd. All rights reserved.

A difference was observed in the reactivity of alcohols and ethers toward free electrons. Whereas the lowest core-excited state of the negative ion-a 2(n,3s2) Feshbach resonance-of the alcohols readily dissociates by losing a hydrogen atom, ethers show no observable signal from this resonance. This difference in reactivity has a parallel in the anomalous shapes and energies of the parent states...

Chemistry Department, College of Science, University of Texas, El Paso, T X 79968, USA Z. Naturforsch. 84b, 614-620 (1979); received September 11, 1978 Relative Basicity Parameter, Conductivity of Protonated Ethers, Calculation of PKA'S for R20H+ It is shown in this paper that a consistent set of values of pKBH+ for 24 ethers, in good agreement with the few which have been obtained b y other me...