Sulfide aliphatic

Sulfides Aliphatic halogenated solvents (1—2 dichloroethane, 1—1-1 trichloroethane (trichloroethylene)... 

Chemoselective Deo iQtgenation of Sulfoxides. DBBS is an exceptionally effective reagent for the rapid deoxygenation of sulfoxides to sulfides. Aliphatic and aromatic sulfoxides undergo deoxygenation in <15 min at room temperature in CH2CI2 to afford sulfides in excellent chemical yields (eq 24). ... 

More than 70 degradation products have been identified. In addition to simple compounds, such as hydrogen sulfide, ammonia, formaldehyde, acetaldehyde, formic acid and acetic acid, dozens of other minor sulfur compounds are formed aliphatic sulfides, aliphatic carbonyl compounds with a thiol group, furans containing sulfur in the molecule (including the previously mentioned meaty aroma character imparting compound 2-methyl-3-furanthiol), thiophenes, thiazoles and alicycHc and heterocycHc bicycHc sulfur... 

Sulfur Compounds. All crude oils contain sulfur in one of several forms including elemental sulfur, hydrogen sulfide, carbonyl sulfide (COS), and in aliphatic and aromatic compounds. The amount of sulfur-containing compounds increases progressively with an increase in the boiling point of the fraction. A majority of these compounds have one sulfur atom per molecule, but certain aromatic and polynuclear aromatic molecules found in low concentrations in crude oil contain two and even three sulfur atoms. Identification of the individual sulfur compounds in the heavy fractions poses a considerable challenge to the analytical chemist. 

Monobasic carboxylic acids with an a-methyl group Esters of aliphatic dibasic carboxylic acids Cyclic sulfides... 

Poly sulfide Polymers. These polymers are made up of aliphatic hydrocarbon units connected by di-, tri- or tetrasulfide links. The synthetic rubber found useful in ordn has hydrocarbon units linked by either O or formal segments. The polymers are usually prepd by the condensation of a suitable organic dihalide, usually the chloride, with aq Na polysulfide. According to Ref 8, the most practical organic dichloride is dichlorodiethylformal viz, Bis[ 2[Pg.827]

Ethyleneimine reacts with (p-tolylsulfonyl)acetylene to give only the (Z)-product 115 via trans addition (equation 91), while primary and secondary aliphatic amines afford ( )-products76. With nonterminal acetylenes such as l-(ethylsulfonyl)-l-propyne, the reactions of ethyleneimine, n-propylamine and f-butylamine give mixtures of ( )- and (Z)-adducts. The double conjugate addition of sodium sulfide, selenide and telluride to bis(l-propynyl)sulfone (116) produces heterocycles (117) as illustrated in equation 9277. 

Reaction of aliphatic aldehydes with H2S and TCS 14 at room temperature in the presence of pyridine leads to the adducts 596, which can be converted by NaH in DMF, via the adducts 597 and the intermediate thioaldehydes 598, into their sodium salts 599. These sodium salts 599 can be trapped by alkyl- or aUyl hahdes in up to 91% yield to give the vinyl sulfides 600 [147] (Scheme 5.47). 

Interest in the possible persistence of aliphatic sulfides has arisen since they are produced in marine anaerobic sediments, and dimethylsulfide may be implicated in climate alteration (Charlson et al. 1987). Dimethylsnlfoniopropionate is produced by marine algae as an osmolyte, and has aronsed attention for several reasons. It can be the source of climatically active dimethylsulfide (Yoch 2002), so the role of specific bacteria has been considered in limiting its flux from the ocean and deflecting the prodncts of its transformation into the microbial sulfur cycle (Howard et al. 2006). 

In this study we examine the generalities in reductive alkylation however, since the subject is vast, we limited ourselves to the interaction of aromatic and aliphatic primary amines and diamines with ketones. The ketones examined include the cyclic ketone, cyclohexanone, and aliphatic ketones such as acetone, and methyl isobutyl ketone (MIBK). We limited our study to sulfided and unsulfided Pt and Pd catalysts supported on activated carbon that were commercially available from Evonik Degussa Corporation. 

Several of the lower molecular weight aliphatic compounds, in a mixture, are part of the roasted coffee aroma. A nine-compound mixture with roasted coffee aroma contained isopentane, n-hexane, acetaldehyde, dimethyl sulfide, propanal, isobutanal, isopentanal, methanol, and 2-methylfuran.20 In addition, the freshness of aroma and taste has been correlated with 2-methylpropanal and diacetyl. When the concentration of these falls off, so does the taste.21 Other aliphatic compounds that are steadily lost from ground roasted coffee, unless it is vacuum packaged, include methyl formate, methyl acetate, methyl thioacetate, and acetone.22 The concentrations in roast coffee for four compounds whose contribution to the fresh flavor have long been known are dimethyl sulfide (4 ppm), methyl formate (12 ppm), isobutanal (20 ppm), and diacetyl (40 ppm). The taste thresholds are 0.1, 0.5, 0.5, and 1.0 ppm, respectively, in the brew made with 5 g coffee per 100 ml water.15... 

---