Aromatic thiols

There have been fewer studies of the reactions of M ions with potential ligand molecules. Laser ablation, which has been the major ionization source for the production of bare metal ions, produces very few negative ions. Electron impact with low-energy electrons (12 eV) of metal carbonyls has been used to produce [Co(CO)4]- and Fc( CO)4 from Co2(CO)8 and Fe(CO)5. Collision-induced dissociation of these two anions produced Co- and Fc, which could be isolated. Both Co- and Fe were reacted with H2S, aliphatic thiols, aromatic thiols, CS2, and disulfides (153). Reactions with H2S gave the metal monosulfide anion [MS]-, which reacted with H2S by two pathways. 

Alkane thiols/aromatic thiols on Au(lll) surface Li 1998 Carbonate Fan 1994 Generic Mayo 1990 Li" vdW parameters Castonguay 1992b Nickel porphyrins Jentzen 1995... 

B. Functional Groups — Preparation, reactions, and interconversions of alkanes, alkenes, alkynes, dienes, alkyl halides, alcohols, ethers, epoxides, sulfides, thiols, aromatic compounds, aldehydes, ketones, carboxylic acids and their derivatives, amines... 

Some S-glucuronides are formed from aliphatic thiols, aromatic thiols and dithiocarboxylic acids. As for C-glucuronidation, this reaction is seen in humans for 1,3-dicarbonyl drugs, such as sulfinpyrazone. 

The CHARMm force field [20] was developed particularly for biological macromolecules, and has become a main force field for investigating biological systems. Kollman and co-workers [21,22] have fitted the benzene-cation interaction very accurately with fliree-body term force fields by including polarizability. Weaver and Donini [23] have also validated the applicability of CHARMm for benzene-cation interaction. Therefore, this study focuses on the aromatic-aliphatic, aromatic-aromatic, aromatic-amide(S), aromatic-amide(B), aromatic-thiol, aromatic-amine, and aromatic-alcohol interactions. 

As will be shown, the original CHARMm parameters can produce IPESs in good agreement with those calculated by the CP-corrected MP2 method for aromatic-aliphatic, aromatic-amide(S), and aromatic-amide(B) interactions. However, for aromatic-aromatic, aromatic-thiol, aromatic-amine, and aromatic-alcohol interactions, the original parameters cannot reproduce the IPESs which match CP-corrected MP2 results. Therefore, the Lennard-Jones parameters for the important atom pair in these four interactions were selected to be optimized. The original and optimized CHARMm Lennard-Jones parameters for these chosen atom pairs are collected in Table 1 for each of these four interactions. 

Residue functionality Heterocyclic, phosphoesteric Amino, carboxyl, hydroxy, phenolic thiol, aromatic, heterocyclic Carbonyl, hydroxy, amino, carboxylic... 

Aromatic Alcohols Aromatic Amino Acids Aromatic Amino Alcohols Aromatic Thiols Aromatic Amines Aromatic Sulfoxides Mandelic Acid Analogs Aryl-Substitute Phthalides Aryl-Substituted Lactams Aryl-Substituted Succinimides Aryl-Substituted Hydantoins a-Hydroxy-a-Aryl Phosphonates Aryl Propionic Acids Phenoxy benzy 1 amine s (P-Blockers)... 

Hydrogen Abstraction. Reactions of (1) with a variety of organic compounds such as amines, alcohols, thiols, aromatics, and even saturated hydrocarbons, proceed by hydrogen abstraction and addition of an OSO2F moiety (R-H R0S02F). For example, methane gives a mixture of methyl fluorosulfate and methylene difluorosulfate. Methyl fluorosulfate also gives methylene difluorosulfate in reaction with (1) Hexafluoropro-pane and propionic acid react in accordance with eqs 4 and 5. 

Various S-nucleophiles are allylated. Allylic acetates or carbonates react with thiols or trimethylsilyl sulfide (353) to give the allylic sulfide 354[222], Allyl sulfides are prepared by Pd-catalyzed allylic rearrangement of the dithio-carbonate 355 with elimination of COS under mild conditions. The benzyl alkyl sulfide 357 can be prepared from the dithiocarbonate 356 at 65 C[223,224], The allyl aryl sufide 359 is prepared by the reaction of an allylic carbonate with the aromatic thiol 358 by use of dppb under neutral condi-tions[225]. The O-allyl phosphoro- or phosphonothionate 360 undergoes the thiono thiolo allylic rearrangement (from 0-allyl to S -allyl rearrangement) to afford 361 and 362 at 130 C[226],... 

Aromatic nitriles or nitrogen heterocycles Indicates either CHO or C2H5 Indicates either CH2O or NO Thiols... 

The addition of aromatic and aUphatic thiols, RSH and ArSH, and a thioacetic acid to isoprene yields mainly the trans-l,4-adduct (56). The aromatic thiyl radicals, ArS , add almost entirely to the first carbon atom however, aUphatic thiyl radicals, RS, also add to the fourth C atom in significant amounts. 

Although aminyl radicals are stable towards oxygen, they can oxidi2e other aromatic amines, phenols and thiols (10), and regenerate the diarylamine. Thus, mixtures of phenols and diarylamines frequendy show better antioxidant activity than either one alone. This is called synergism. 

Sulfonic acids are prone to reduction with iodine [7553-56-2] in the presence of triphenylphosphine [603-35-0] to produce the corresponding iodides. This type of reduction is also facile with alkyl sulfonates (16). Aromatic sulfonic acids may also be reduced electrochemicaHy to give the parent arene. However, sulfonic acids, when reduced with iodine and phosphoms [7723-14-0] produce thiols (qv). Amination of sulfonates has also been reported, in which the carbon—sulfur bond is cleaved (17). Ortho-Hthiation of sulfonic acid lithium salts has proven to be a useful technique for organic syntheses, but has Httie commercial importance. Optically active sulfonates have been used in asymmetric syntheses to selectively O-alkylate alcohols and phenols, typically on a laboratory scale. Aromatic sulfonates are cleaved, ie, desulfonated, by uv radiation to give the parent aromatic compound and a coupling product of the aromatic compound, as shown, where Ar represents an aryl group (18). 

The reactive species that iaitiate free-radical oxidatioa are preseat ia trace amouats. Exteasive studies (11) of the autoxidatioa mechanism have clearly estabUshed that the most reactive materials are thiols and disulfides, heterocycHc nitrogen compounds, diolefins, furans, and certain aromatic-olefin compounds. Because free-radical formation is accelerated by metal ions of copper, cobalt, and even iron (12), the presence of metals further compHcates the control of oxidation. It is difficult to avoid some metals, particularly iron, ia fuel systems. 

The utility of methanesulfinyl chloride lies in its great chemical reactivity. Through its ready hydrolysis, it serves as a convenient source of methanesulfinic acid. It reacts at low temperature with aromatic amines to form sulfinamides, and with alcohols to form sulfinate esters. When it is hydrolyzed in the presence of an equimolar quantity of sulfenyl chloride, a thiol-sulfonate ester is produced. 

Arylidene-5-oxazolones undergo a ring-opening reaction with aromatic thiols and a second mole of thiol is then incorporated to give products such as 48. ... 

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