Ethanethiol

Abstract: The scope and limitations of reagents for the cleavage of ethers are discussed. The reagents are conveniently classified in the five main headings. Selectivity patterns of some of the reagents are discussed in cases where sufficient data has been given in the literature. 1. Introduction 2. Acidic Reagents 2.1. Bronsted Acids 2.2. Lewis Acids 3. Basic Reagents 3.1. Alkali Hydroxides 3.2. Alkali Alkoxides 3.3. Alkali Amides 3.4. Alkali Metals 3.5. Organo-Alkali Metal Compounds 3.6. Sodium Cyanide/Dimethyl Sulfoxide 3.7. Sodium Ethanethiolate 3.8. Sodium Thiocresolate 3.9. Lithium Iodide 3.10. Sodium Benzeneselenolate 4. Miscellaneous Reagents 4.1. Iodotrimethylsilane 4.2. Iodotrichlorosilane 4.3. Dichloroiodomethylsilane 4.4. Bromotrimethylsilane 4.5. Alkylthiotrimethylsilanes 4.6. Ethanethiol or Ethanedithiol/Boron Trifluoride Etherate 4.7. Aluminium Halide/Thiol Systems 4.8. Acetyl Iodide and Pivaloyl Iodide 4.9. Diiodomethyl Ether/Hydrogen Iodide 5. Reductive Cleavage of Ethers 5.1. Lithium Tris[t-butoxy]aluminium Hydride/Triethylborane Complex 5.2. Hydrogenolysis 6. Oxidative Cleavage of Ethers 6.1. Ceric Ammonium Nitrate 6.2. Silver Oxide 6.3. Dichlorodicyanoquinone 6.4. Tris[p-bromophenyl]ammonium Hexachloroantimonate 7. Photochemical Cleavage of Ethers 8. Selectivity in Ether Cleavage 8.1. Stereoelectronic Characteristics of the Ether-Cleaving Agent 8.2. Structural Features of the Groups Cleaved 8.3. Molecular Environment of the C-O Bond not Undergoing Cleavage 9. Addendum

Abstract: A general synthetic approach leading to well-defined, water-soluble gold nanoparticles is described that involves a simple, interfacial ligand exchange reaction between a 1.4 nm phosphine-passivated precursor and an anionic or cationic thiol-containing ligand. We demonstrate the utility of this route by synthesizing water-soluble gold nanoparticles that are stabilized by either an anionic ligand (2-mercaptoethanesulfonate), a cationic ligand (2-(dimethylamino)ethanethiol hydrochloride), or a mixture of both ionic and phosphine ligands. Although the course of the ligand exchange process depends on the nature of the incoming ligand, each of these nanoparticle products retain the small core size and narrow size distribution of the starting particle (1.4 ± 0.4 nm). The stabilities of these nanoparticles to elevated temperature, extremes of pH, and added salt are reported and found to depend on the nature of the exposed headgroups on the ligand shell. Salt-induced aggregation is not observed in any of the case...

Abstract: An enzyme electrode for the detection of V-type nerve agents, VX (O-ethyl-S-2-diisopropylaminoethyl methylphosphonothioate) and R-VX (O-isobutyl-S-2-diethylaminoethyl methylphosphonothioate), is proposed. The principle of the new biosensor is based on the enzyme-catalyzed hydrolysis of the nerve agents and amperometric detection of the thiol-containing hydrolysis products at carbon nanotube-modified screen-printed electrodes. Demeton-S was used as a nerve agent mimic. 2-(Diethylamino)ethanethiol (DEAET) and 2-(dimethylamino)ethanethiol (DMAET), the thiol-containing hydrolysis product and hydrolysis product mimic of R-VX and VX, respectively, were monitored by exploiting the electrocatalytic activity of carbon nanotubes (CNT). As low as 2 μM DMAET and 0.8 μM DEAET were detected selectively at a low applied potential of 0.5 V vs Ag/AgCl at a CNT-modified mediator-free amperometric electrode. Further, the large surface area and the hydrophobicity of CNT was used to immobilize organophosphorus hydrolase mutan...