Secondary amines sulfide

Generally, isolated olefinic bonds will not escape attack by these reagents. However, in certain cases where the rate of hydroxyl oxidation is relatively fast, as with allylic alcohols, an isolated double bond will survive. Thepresence of other nucleophilic centers in the molecule, such as primary and secondary amines, sulfides, enol ethers and activated aromatic systems, will generate undesirable side reactions, but aldehydes, esters, ethers, ketals and acetals are generally stable under neutral or basic conditions. Halogenation of the product ketone can become but is not always a problem when base is not included in the reaction mixture. The generated acid can promote formation of an enol which in turn may compete favorably with the alcohol for the oxidant. 

In an opposite manner to bases such as 1 and 2 in terms of reactivity, polymer-supported tosyl chloride equivalent 14 is able to capture alcohols as polymer-bound sulfonates 15, which are released as secondary amines, sulfides and alkylated imidazoles with primary amines, thiols and imidazoles as nucleophiles in a substitution process (Scheme 6) [24]. This technique has further been extended for the preparation of tertiary amines [25] and esters [26]. Excess of amine was scavenged by polymer-supported isocyanate 16 [27, 28] while excess of carboxylic acid was removed by treatment with aminomethylated polystyrene 17. 

Primary and secondary amines, double bonds, aldehydes, sulfides and certain aromatic and dihydroaroraatic systems are also oxidized by chromium VI reagents under standard hydroxyl oxidizing conditions. Amines are commonly protected by salt formation or by conversion to amides. Aldehydes and... 

Diisopropanolamine Systems. Diisopropanolamine (DIPA) is a secondary amine used in the Shell ADIP process to sweeten natural gas. DIPA systems are similar to MEA systems but offer the following ad an-tages carbonyl sulfide (COS) can be removed and regenerated easily and the system is generally noncorrosive and requires less heat input. 

Salts of dithiocarbamic acid can be prepared by the addition of primary or secondary amines to carbon disulfide. This reaction is similar to 16-9. Hydrogen sulfide can be eliminated from the product, directly or indirectly, to give isothiocyanates (RNCS). Isothiocyanates can be obtained directly by the reaction of primary amines and CS2 in pyridine in the presence of DCC. ° In the presence of diphenyl phosphite and pyridine, primary amines add to CO2 and to CS2 to give, respectively, symmetrically substituted ureas and thioureas ... 

Diazonium ions form stable adducts with certain nucleophiles such as secondary amines and sulfide anions.85 These compounds can be used as precursors of diazonium ion intermediates. 

These compounds are prepared from bisimidazolyl sulfide (jV -thiodiimidazole) and secondary amines such as piperidine.[37]... 

If one or more of the hydrogen atoms of a non-metal hydride are replaced formally with another group, R—e.g., alkyl residues—then derived compounds of the type R-XHn-i, R-XHn-2-R, etc., are obtained. In this way, alcohols (R-OH) and ethers (R-O-R) are derived from water (H2O) primary amines (R-NH2), secondary amines (R-NH-R) and tertiary amines (R-N-R R") amines are obtained from ammonia (NH3) and thiols (R-SH) and thioethers (R-S-R ) arise from hydrogen sulfide (H2S). Polar groups such as -OH and -NH2 are found as substituents in many organic compounds. As such groups are much more reactive than the hydrocarbon structures to which they are attached, they are referred to as functional groups. 

Abstract This chapter principally concerns oxidations of organic substrates containing N, O, S, P, As and Sb. Oxidations of amines are covered first, including primary amines to nitriles or amides secondary amines to imines or other products tertiary amines to N-oxides or other prodncts (Section 5.1) and the oxidation of amides (5.2). Oxidation of ethers to esters or lactones follows (5.3), then of sulfides to sulfoxides or sulfones (5.4) and of phosphines, arsine and stibines to their oxides (5.5). A final section (5.6) concerns such miscellaneous oxidations not covered by other sections in the book. 

Exxon s Flexsorb SE solvents achieve high hydrogen sulfide selectivity by virtue of their molecular structure. These solvents are sterically hindered secondary amines. A bulky molecule is used to shield the available hydrogen radical on the nitrogen atom and prevent the insertion of carbon dioxide. The reaction with hydrogen sulfide is not sensitive to the amine s structure, so the steric hinderance affords higher hydrogen sulfide selectivity. 

Alkylation or acylation of ketones, sulfides, and amines. This reagent generally reacts with alcohols or carboxylic acids to form 2,2,2-trifluoroethyl ethers or esters in satisfactory yields, except in the case of alcohols prone to dehydration. The reaction of these ethers provides a simple synthesis of unsymmctrical sulfides (equation I). A similar reaction can be used for preparation of secondary amines or amides (equation II). Enolatc anions (generated from silyl cnol ethers with KF) can be alkylated or acylated with a or b (equation III). Use of Grignard reagents in this type of coupling results in mediocre yields. 

The thiophene ring is opened and sulfur extruded as hydrogen sulfide when 3,4-dinitrothiophene is reacted with piperidine. The product contains two nitroenamine units coupled to each other (Scheme 140). Other secondary amines react similarly (69CC549). Secondary aliphatic amines also react with 2-nitrothiophene to form the nitrodienamines (426) in 50-80% yield. It is believed that the reaction involves addition of the amine at position 5, followed by proton transfer and ring opening to give the thiol which, in the presence of air, oxidatively dimerizes to (426) (Scheme 141). In one case the thiol has been trapped as the silver salt and methylated (74JCS(P1)2357). 

In lieu of preparing and handling large amount of ethylene sulfide, ethyl 2-mercaptoethylcarbonate (XII) has been employed uiib advantage in the mercaptoethylation of primary and secondary amines.8 Introduction of this carbonate into a refluxing solution ol amine in toluene promotes its decomposition to ethylene suJfi.K carbon dioxide and ethanol. The ethylene sulfide react with the amine to give the 2-aminoethanethiol (Eq, 47). 

In the case of cationic complexes with unsaturated macrocycles two molecules of nucleophile, such as ammonia, amines and alkoxides, add to carbon atoms of two inline groups. For example, the reaction of [Ni(Bzo[16]octaeneN4)](C104)2 (Table 106) with sodium methoxide or ethoxide yields the compounds (395),2860 while with secondary amines and diamines complexes of type (396) are obtained.28 1 The reaction of (396) with acetone at room temperature yields complex (397) where the enolate anion of acetone, MeC(0)CH2, replaces the diethylamide group (Scheme 58). 2862 The addition of molecules such as bis(2-hydroxyethyl)methylamine and bis(2-hydroxyethyl) sulfide, HOCH2CH2YCH2CH2OH (Y = NMe, S) results in the formation of derivatives which possess one more coordination site just above the plane of the macrocyclic donors (398).2863... 

Platinum sulfide appeared superior to palladium for the reductive alkylation of piperidine with acetone. A more carefully controlled comparison of platinum sulfide with palladium and with platinum is shown in Table 2 for the reaction of N-ethylcyclohexylamine with cyclohexanone. Platinum gave a very poor conversion of the starting secondary amine (27%) and a correspondingly low yield of the tertiary amine product (22%), although the yield based on conversion was good (81%). The... 

These results illustrate the practicality of preparing trialkylamines by the reductive alkylation of dialkylamines with aliphatic ketones. Excellent yields are obtained, particularly with the more reactive and less hindered ketones, such as cyclohexanone and acetone, and with the less hindered secondary amines. Platinum sulfide, or other platinum metal sulfides, are the catalysts of choice when more hindered reagents require more severe operating conditions. 

Thiolate anions37 38 and oxime alkoxides38 react under phase transfer conditions to give aryl sulfides and O-aryl oximes, respectively the o-dichloro benzene complex can be converted selectively to the monosubstitution product (equation 9). The arylation of oximes leads to a simple process for benzofuran formation (equation 10). Simple primary and secondary amine nucleophiles react smoothly in the absence of added base, in a very general and efficient process for aniline derivatives.49... 

For example, polymers having hydroxyl end groups can be prepared by reaction of polymer lithium with epoxides, aldehydes, and ketones III-113). Carboxylated polymers result when living polymers are treated with carbon dioxide (///) or anhydrides (114). When sulfur (115, 116), cyclic sulfides (117), or disulfides (118) are added to lithium macromolecules, thiol-substituted polymers are produced. Chlorine-terminus polymers have reportedly been prepared from polymer lithium and chlorine (1/9). Although lithium polymers react with primary and secondary amines to produce unsubstituted polymers (120), tertiary amines can be introduced by use of p-(dimethylamino)benzaldehyde (121). 

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