Sulphoxides aliphatic

Cates and Meloan56 separated aliphatic and aromatic sulphoxides on Carbowax 20M... 

If a dilute solution of hydrogen peroxide in dry acetonitrile is added to a solution of a sulphoxide and an iron(II) salt in dry acetonitrile then the sulphone is produced in quantitative yield34. This latter reaction works equally well for aliphatic and aromatic sulphoxides and is thought to involve oxygen transfer by the reaction of a ferryl ion with the sulphoxide, as shown in equation (12). 

Aldol condensation 616, 618, 619, 829 Aliphatic sulphoxides, mass spectra of 126, 127... 

Sulphonylthioureas, mass spectra of 158 Sulphoxides - see also Alkoxysulphoxides, Aminosulphoxides, -Anilinosulphoxides, Cyanosulphoxides, a, /i-Dihalosulphoxides, Disulphoxides, Enaminosulphoxides, Episulphoxides, Epoxysulphoxides, Halosulphoxides, Hydroxysulphoxides, /i-Iminosulphoxides, Ketosulphoxides, a-Lithiosulphoxides, /i-Oximinosulphoxides, Persulphoxides, a-Thioamidosulphoxides addition reaction of 619-623, 836-845 aliphatic - see Aliphatic sulphoxides alkenyl - see Alkenyl sulphoxides alkyl aryl - see Alkyl aryl sulphoxides /(-alkylthio(arylthio)ethyl - see /J-Alkylthio(arylthio)ethyl sulphoxides... 

With DMSO and aliphatic sulphoxides, dry perchloric acid also forms very unstable salts. If the acid concentration is 70% or more, when it comes into contact with DMSO, this gives rise to an immediate explosion. Aromatic sulphoxides give rise to far less dangerous interactions. 

Figure 1.5 High-field (aliphatic) regions of 400 MHz H Hahn spin-echo NMR spectra of (a) E-199 culture medium (b) as (a) but following a 2 h incubation with neutrophils at 37°C (c) as (b) but incubated in the presence of 1.00 x 10 mol/dm phorbol 12-myrlstate 13-acetate (PMA). For abbreviations, see Fig. 1.2 with Met, methionine-S-Ctl3 group resonance MetSO, methionine sulphoxide-SO-CHs group resonance. The 2.245 p.p.m. singlet detectable in spectrum (c) arises from the -CH3 groups of acetone, the solvent in which PMA was...

Phenylphosphinic acid and dialkyl sulphoxides are alternatives for, respectively, the reducing agent (formic acid) and the alkylating agent (an aldehyde) used for the TV-alkylation of secondary aliphatic amines (the Eschweiler-Clarke procedure) (equation 55b)166. 

The reaction of aq/i-cpoxy sulphoxides with aliphatic or aromatic amines affords a-amino ketones, e.g. equation 94293. 

Roberts269 has studied the hydrolysis of series of ethyl esters271 272 and alkyl benzoates273 in a limited range of water-dimethyl sulphoxide mixtures in some detail, and finds that the data for the hydrolysis of aliphatic ethyl esters (at 35°C in 85% dimethyl sulphoxide-water) fit the modified Taft equation (eqn. 5, p. 132). The values of p = 1.88 and 8 = 0.88 can be compared with p = 2.39 and 8 = 1.04 for 85% EtOH-water at the same temperature. The polar reaction constant is reduced in the dipolar aprotic solvent, consistent with a reduced degree of bond formation in the transition state, expected if the activity of the hydroxide ion is increased. However, Roberts considers that the sensitivity to steric effects, as measured by 8, would be reduced more substantially if bond formation were less advanced. It is difficult to accept this argument, since we... 

Davies MJ, Gilbert BC, Norman ROC (1984) Electron spin resonance, part 67. Oxidation of aliphatic sulphides and sulphoxides by the sulphate radical anion (S04 ) and of aliphatic radicals by the peroxydisulphate anion S Os2 ). J Chem Soc Perkin Trans 2 503-509 Dizdaroglu M, Gajewski E, Reddy P, Margolis SA (1989) Structure of a hydroxyl radical induced DNA-protein cross-link involving thymine and tyrosine in nucleohistone. Biochemistry 28 3625-3628... 

Smakman, R. and deBoer, T.J., The mass spectra of some aliphatic and alicyclic sulphoxides and sulphones, Org. Mass Spectrosc., 3, 1561, 1970. 

The reaction of sulphides with (dichloroiodo)benzene can lead to several kinds of products depending on the substrate and the reaction conditions [19]. Sulphides of great structural diversity (aliphatic, aromatic, heterocyclic) were oxidized efficiently by (dichloroiodo)benzene (one equivalent) in aqueous pyridine. The reaction was almost instantaneous and not noticeably sensitive to steric or electronic effects. Ethylenic double bonds were not attacked under these conditions however, in vinylic sulphides containing an electron-withdrawing group (COOH or RSO) ft- to the sulphur atom the oxidation was accompanied by nucleophilic attack to the double bond resulting in a mixture of products. The method is suitable for the preparation of I80-labelled sulphoxides using small quantities of H2,80. 

By far, the most extensive studies and applications of (dichloroiodo)benzene involved the direct conversion of aliphatic sulphides into a-chlorosulphoxides. Related results were reported for the chlorination of sulphoxides to a-chlorosulphoxides, especially from the stereochemical point of view. Generally,... 

Lewis bases like aliphatic or aromatic amines, sulphoxides, phosphorous derivatives form adducts with / -diketonates, by recrystallization of the hydrated lanthanide fi-diketonates in a solution of the substrate [51,52]. The adducts have also been prepared by extraction of lanthanide salt with a stoichiometric mixture of the /5-diketone and a Lewis base. Alternatively it can be prepared by increasing the pH of an ethanolic-water solution of lanthanide salt, /5 -diketone and the organic substrate. 

Kishore K, Asmus KD. (1989) Radical cations from one-electron oxidation of aliphatic sulphoxides in aqueous solution. A radiation chemical study. J Chem Soc Perkin Trans II2079-20S4 . 

The compound referred to as 3-methylpyrazolone A ought to show a quartet and a triplet in the aliphatic region, the former for the ring CTT group. However, only a quartet is observed in the sp shift range in hexadeuteriodimethyl sulphoxide whilst at 89.2 ppm... 

Aromatic and aliphatic sulphides, thioethers, thiols, thioamides and thiocarbamates may undergo oxidation to form sulphoxides and then, after further oxidation, sulphones (figure 4,23). This is catalysed by a microsomal mono-oxygenase requiring NADPH and cytochromes P-450. The FAD-containing mono-oxygenases will also catalyse -oxidation reactions. 

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