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Reaction with carbonyl sulfide

Alkali-immobile dye-releasing quinone compounds, 19 293-294 Alkali lignins, 15 19-20 Alkali manganate(VI) salts, 15 596 Alkali manganates(V), 15 592 Alkali-metal alkoxide catalysts, 10 491 Alkali-metal alkoxides, effects of, 14 252 Alkali-metal alkylstannonates, 24 824 Alkali-metal fluoroxenates, 17 329-330 Alkali-metal hydrides, 13 608 Alkali-metal hydroxides, carbonyl sulfide reaction with, 23 622 Alkali-metal metatungstates, 25 383 Alkali-metal perchlorates, 18 211 Alkali-metal peroxides, 16 393... [Pg.29]

E. Alper, M. al-Roweih, and W. Bouhomra [Chem. Eng. J., 55, 53-59 (1994)] stndied the kinetics of the reaction of carbonyl sulfide (A) with 2-amino-2-methyl-l-propanol... [Pg.265]

Hydroxy-THISs react with electron-deficient alkynes to give nonisol-able adducts that extrude carbonyl sulfide, affording pyrroles (23). Compound 16 (X = 0) seems particularly reactive (Scheme 16) (25). The cycloaddition to benzyne yields isoindoles in low- yield. Further cyclo-addition between isoindole and benzyne leads to an iminoanthracene as the main product (Scheme 17). The cycloadducts derived from electron-deficient alkenes are stable (23, 25) unless highly strained. Thus the two adducts, 18a (R = H, R = COOMe) and 18b (R = COOMe, R = H), formed from 7, both extrude furan and COS under the reaction conditions producing the pyrroles (19. R = H or COOMe) (Scheme 18). Similarly, the cycloadduct formed between 16 (X = 0) and dimethylfumarate... [Pg.9]

Carbon disulfide [75-15-0] is a clear colorless liquid that boils at 46°C, and should ideally be free of hydrogen sulfide and carbonyl sulfide. The reaction with alkaU cellulose is carried out either in a few large cylindrical vessels known as wet chums, or in many smaller hexagonal vessels known as dry chums. In the fully continuous viscose process, a Continuous Belt Xanthator, first developed by Du Pont, is used (15). [Pg.347]

Ma.nufa.cture. Nickel carbonyl can be prepared by the direct combination of carbon monoxide and metallic nickel (77). The presence of sulfur, the surface area, and the surface activity of the nickel affect the formation of nickel carbonyl (78). The thermodynamics of formation and reaction are documented (79). Two commercial processes are used for large-scale production (80). An atmospheric method, whereby carbon monoxide is passed over nickel sulfide and freshly reduced nickel metal, is used in the United Kingdom to produce pure nickel carbonyl (81). The second method, used in Canada, involves high pressure CO in the formation of iron and nickel carbonyls the two are separated by distillation (81). Very high pressure CO is required for the formation of cobalt carbonyl and a method has been described where the mixed carbonyls are scmbbed with ammonia or an amine and the cobalt is extracted as the ammine carbonyl (82). A discontinued commercial process in the United States involved the reaction of carbon monoxide with nickel sulfate solution. [Pg.12]

Occurrence ndPreparation. Carbonyl sulfide is formed by many high temperature reactions of carbon compounds with donors of oxygen and sulfur. A principal route is the foUowiag reaction (30) ... [Pg.130]

This equihbrium favors COS up to ca 500°C. At higher temperatures, COS dissociates increasingly, eg, to 64% at 900°C. The reaction may be mn at 65—200°C to produce carbonyl sulfide if an alkaline catalyst is used (31). A Rhc ne-Poulenc patent describes the manufacture of carbonyl sulfide by the reaction of methanol with sulfur at 500—800°C (32). [Pg.130]

Uses. There may be some captive use of carbonyl sulfide for production of certain thiocarbamate herbicides (qv). One patent (38) describes the reaction of diethylamine with carbonyl sulfide to form a thiocarbamate salt which is then alkylated with 4-chloroben2yl haUde to produce 3 -(4-chloroben2yl) A[,A/-diethylthiocarbamate [28249-77-6] ie, benthiocarb [28249-77-6]. Carbonyl sulfide is also reported to be useful for the preparation of abphatic polyureas. In these preparations, potassium thiocyanate and sulfuric acid are used to first generate carbonyl sulfide, COS, which then reacts with a diamine ... [Pg.131]

Reduction of sulfur dioxide by methane is the basis of an Allied process for converting by-product sulfur dioxide to sulfur (232). The reaction is carried out in the gas phase over a catalyst. Reduction of sulfur dioxide to sulfur by carbon in the form of coal has been developed as the Resox process (233). The reduction, which is conducted at 550—800°C, appears to be promoted by the simultaneous reaction of the coal with steam. The reduction of sulfur dioxide by carbon monoxide tends to give carbonyl sulfide [463-58-1] rather than sulfur over cobalt molybdate, but special catalysts, eg, lanthanum titanate, have the abiUty to direct the reaction toward producing sulfur (234). [Pg.144]

Other components in the feed gas may react with and degrade the amine solution. Many of these latter reactions can be reversed by appHcation of heat, as in a reclaimer. Some reaction products cannot be reclaimed, however. Thus to keep the concentration of these materials at an acceptable level, the solution must be purged and fresh amine added periodically. The principal sources of degradation products are the reactions with carbon dioxide, carbonyl sulfide, and carbon disulfide. In refineries, sour gas streams from vacuum distillation or from fluidized catalytic cracking (FCC) units can contain oxygen or sulfur dioxide which form heat-stable salts with the amine solution (see Fluidization Petroleum). [Pg.211]

Carbon disulfide is essentially unreactive with water at room temperature, but above about 150°C in the vapor phase some reaction occurs forming carbonyl sulfide (carbon oxysulfide) [463-58-1] and hydrogen sulfide [7783-06-4]. Carbonyl sulfide is an intermediate in the hydrolysis reaction ... [Pg.27]

These reactions are reversible by changing the system temperature. ME A also reacts with carbonyl sulfide (COS) and carbon disulfide (CSi) to form heat-stable salts that cannot be regenerated. At temperatures above 245°F a side reaction with CO2 exists that produces oxazolidone-2. a heat-stable salt, and consumes MEA from the process. [Pg.164]

TliCNC reactions are reversible. DEA reacts with carbonyl sulfide (CUS) and carbon disulfide (CS2) to form compounds that can be regenerated in the stripping column. Therefore, COS and CS2 are removed without a loss i)f DEA. Typically, DEA systems include a carbon filter but do not include a reclaimer. [Pg.166]

Preparation Of Thiol Acids, Thiol Esters And Amides By Reactions Of Carbonyl Sulfides With Grignard Reagents," Katritzky. A.R. Moutou, J.-L. Yang, Z. Org. Prep. Proceed. Int., 1995, 27, 361... [Pg.29]

Carius (8) replaced the oxygen in phosphoryl chloride by sulfur. This may be somewhat analogous to the replacement of oxygen in a carbonyl group by sulfur using phosphorus pentasulfide. Prinz (8) used thionyl chloride in his reaction with phosphorus sulfide and De Fazi (2) used carbon tetrachloride in a very interesting preparation of this important intermediate. [Pg.145]

Ugi and Domling have shown that the U-4CR can also be combined with other MCRs, thus creating sequences which involve up to nine different substrates [33]. An example of such an approach is the combination of an Ugi-4CR with the as-yet not mentioned Asinger reaction (A-3CR or A-4CR). The latter allows the formation of thiazolines from ammonia, carbonyl compounds and sulfides [34]. As shown in Scheme 9.7, a mixture of a-bromoisobutyraldehyde, isobutyraldehyde, sodium hy-drogensulfide and ammonia yields the imine 9-38 which, by reaction with t-butyl-isocyanide, methanol, and C02, led to the final product 9-39 [35]. [Pg.547]

The Diels-Alder cycloaddition potential of fused 4-aryldihydropyrimidine mesomeric betaines has been studied. The cross-conjugated thiazinium betaine 317 underwent 1,4-dipolar cycloaddition with electron-rich dipolaro-philes, and thus 1-diethylaminoprop-l-ine gave the pyrido[l,2-tf]pyrimidine 318 by loss of carbonyl sulfide (Equation 34). Reaction of 317b with 1,1-diethoxyethene resulted in the 8-ethoxy analogue of 318 (R = H) <1997JOC3109>. [Pg.302]


See other pages where Reaction with carbonyl sulfide is mentioned: [Pg.419]    [Pg.56]    [Pg.247]    [Pg.491]    [Pg.312]    [Pg.482]    [Pg.357]    [Pg.221]    [Pg.61]    [Pg.217]    [Pg.510]    [Pg.21]    [Pg.18]    [Pg.96]    [Pg.48]    [Pg.198]    [Pg.276]    [Pg.491]   


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