Carbon disulfide Carbonic acid

Fig. 8.11. Tandem reaction consisting of three single reactions mutually transforming heterocumulenes and heteroatom nucleophiles in a one-pot synthesis of an isothiocyanate (1) uncatalyzed addition reaction of heteroatom nucleophile (aniline) + heterocumulene (carbon disulfide) —> carbonic acid derivative (A) (2) heterolysis-initiated /3-elimination of the carbonic acid derivative (D) -> heterocumulene (F = phenylisothiocyanate) + heteroatom nucleophile (thiocar-bonic acid O-ethylester) (3) decomposition of a carbonic acid derivative (D) to a heterocumulene (carbon oxysulfide) and a heteroatom nucleophile (ethanol) via the zwitterion H.

Carbon diselenide Carbon disulfide Carbonic acid Carbonic dihydrazide Carbon monoxide Carbonochloridic acid, 4-nitrophenyl ester Carbonochloridic acid, (4-nitrophenyl)methyl ester Carbonochloridic acid, 2,2,2-trichloroethyl ester Carbonothioic dichloride... 

For the spectrophotometric method, the evolved carbon disulfide is reacted with copper acetate and diethylamine to form a yellow copper complex which can be measured at 435 nm." The recoveries range between 70 and 90%. Reproducibility of this method was improved by reducing the time and the mode of sample pretreatment. Since all alkylenebis(dithiocarbamates) decompose to carbon disulfide by acid degradation, the above analytical methods are not selective. The result is the measured total residues of all alkylenebis(dithiocarbamates) related products. However, this method is recommended as standard method S15 for alkylenebis(dithiocarbamates) by the German Research Association. ... 

Dinitrogen tetraoxide Carbon disulfide Nitrogen oxide Carbon disulfide Permanganic acid Organic materials... 

Hydrazines of type 89 react with various carbonic acid derivatives to furnish cyclized product. Under basic conditions (KOH), in the presence of carbon disulfide or arylisothiocyanates, the cyclized thione 90 is obtained (Scheme 7) <1966JOG3528, 1984JCCS315>. Analogous reactions performed in the absence of base gave 91 as a 3-thiol when performed with carbon disulfide, as a 3-hydroxyl with methyl chloroformate, or as a 3-arylamino with arylisothiocyanates in the presence of dicyclohexylcarbodiimide (Scheme 7) <1986JHC1339, 1992IJB467>. 

The sulfuric acid sludge from sulfuric acid treatment is used frequently as a source (through thermal decomposition) to produce sulfur dioxide (SO2, which is returned to the sulfuric acid plant) and sludge acid coke. The coke, in the form of small pellets, is nsed as a snbstitute for charcoal in the manufacture of carbon disulfide. Sulfuric acid coke is different from other petrolenm coke in that it is pyrophoric in air and also reacts directly with snlfnr vapor to form carbon disulfide. 

Carbomethoxybenzaldehyde, 30, 100 5-Carbomethoxy valeryl chloride, 38, 39 Carbon disulfide, 30, 57 39, 8, 78 Carbonic acid, trithio-, bis(carboxy-methyl) ester, 39, 77 Carbonic-carboxylic anhydrides, 37, 21 Carbon monoxide, 34, 14 Carbon oxysulfide, 32, 103 Carbon tetrachloride, 32, 27 37, 8 Carbonylation, of pyrogallol-1,3-dimethyl ether with hexamethylenetetramine, 31, 92 of pyrrole with dimethylformamide,... 

Cyclotriveratrylene/1180-60-5] (34) is a cyclocondensation product of veratrole with formaldehyde. It possesses a stable trigonal crown conformation and forms crystalline inclusion compounds with benzene, chlorobenzene, toluene, thiophene, decalin, chloroform, acetone, carbon disulfide, acetic acid, and butyric acid (101). Their structures consist of columns of cyclotriveratrylene molecules that are not amenable to close packing and provide channels into which the guests are accommodated. A number of modified host structures, derived from prototype (34) have been prepared. The hexaphenol analogue cyclotricatechylene also yields well-defined channel inclusions (101). They involve mosdy polar guests and the structures are held by hydrogen bonding. 

In the presence of potassium hydroxide, cellulose adds to carbon disulfide (Figure 8.4). In this way potassium xanthate A is produced. It is soluble in water, but restores the water-insoluble cellulose upon addition of acid. The primary protonation product is the dithiocarbonic acid O-cellulose ester B. B reacts just like the unstable carbonic acid derivatives in Figure 8.3, namely via a zwitterion (C) and its decomposition into cellulose (a heteroatom nucleophile)... 

To complete this series of heterocumulene syntheses from carbonic acid derivatives, we here present the acid- and base-catalyzed alcohol elimination from carbamic acid esters (C, Figure 8.10) and the condensation of aniline and carbon disulfide to phenylisothiocyanate (F,... 

Carbon disulfide is the dithio derivative of C02. It is only a weak electrophile. Actually, it is so unreactive that in many reactions it can be used as a solvent. Consequently, only good nucleophiles can add to the C—S double bond of carbon disulfide. For example, alkali metal alkoxides add to carbon disulfide forming alkali metal xan-thates A (Figure 7.4). If one were to protonate this compound this would provide compound B, which is a derivative of free dithiocarbonic acid. It is unstable in the condensed phase in pure form, just as free carbonic acid and the unsubstituted carbamic acid (Formula B in Figure 7.3) are unstable. Compound B would therefore decompose spontaneously into ROH and CS2. Stable derivatives of alkali metal xanthates A are their esters C. They are referred to as xanthic add esters or xanthates. They are obtained by an alkylation (almost always by a methylation) of the alkali metal xanthates A. You have already learned about synthesis applications of xanthic acid esters in Figures 1.32, 4.13, and 4.14. 

The synthesis of 2(3//)-oxazolones by incorporation of carbon atom 2 into a four-atom chain is exemplified by the condensation of phenacylaniline with ethyl chloroformate (equation 138). Benzoxazolones are similarly prepared from o-aminophenols and derivatives of carbonic acid, such as phosgene, diethyl carbonate, urethane (Et02CNH2) or urea (equation 139). The analogous condensation of carbon disulfide or cyanogen bromide with o-aminophenols leads to benzoxazolethiones or 2-aminobenzoxazoles, respectively (equation 140). 

Sulfur trioxide/sulfur dioxide, dimethylformamide, carbon disulfide Chlorosulfonic acid/sulfur dioxide, pyridine... 

Carbohydrates, allyloxycarbonates, 123 carbonates of, 151 chloroformyl esters of, 102 conformational analysis of, 12 reaction of, with carbon dioxide, 129 with carbon disulfide, 135 with carbonic acid, 129 with phosgene in acetone, 105 thermochemical properties of, 21 thiocarbonates of, 157 Carbonic acid, esters, 91,92,151 bis(methyl 3,4-0-isopropylidene-/3-D-arabinopyranoside), 2,2 -, 96 bis(1,2,3,4 - tetra - O - acetyl -/J - D - glucose), 6,6 -, 104 cyclic, 103... 

In the laboratory, the dibromides are the most conveniently and easily prepared. The reaction is generally run at low temperatures. (-20° to 20°) using a solvent, such as chloroform, carbon disulfide, acetic acid, or ether it is sometimes aided by artificial light or sunlight. Heating is usually not recommended because it promotes substitution and dehydro-halogenation. The procedure is illustrated by the addition of bromine to allyl bromide to yield 1,2,3-ttibromopropane (98%). ... 

The reagents used for the completion of the purine heterocycle are essentially the same as those used for the Traubc synthesis. The purine ring is formed by condensation with derivatives of formic acid or other carboxylic acids. Alternatively, formylation of the amino group is accomplished by a mixture of formic acid and acetic anhydride followed by cyclization. Alkyl esters or trialkyl ortho esters are also versatile synthons for ring closure. Moreover, heating in formamide or cyclization with urea or thiourea provides a satisfactory route. Condensations with isothiocyanates show unusual versatility leading to 2-sulfanylpurin-6-ols. From carbonic acid derivatives, cyclization is reported with chlorocarbonic esters, diethyl carbonate or carbon disulfide. 

If only the simplest compounds of carbon are considered (marsh gas, methyl chloride, carbon tetrachloride, chloroform, carbonic acid, phosgene gas, carbon disulfide, prussic acid, etc.), it is striking that the amount of carbon which the chemist has known as the smallest possible, as the atom always combines with four atoms of a monatomic, or two atoms of a diatomic element that in general, the sum of the chemical units of the elements which are bound to one atom of carbon is equal to 4. This leads to the view that carbon is tetratomic (or tetrabasic). ... 

Properties Yellow, deliquescent, crystalline mass. Decomposed by water, d 4.148, mp 96.6C, bp 280C. Soluble in carbon disulfide, hydrobromic acid, hydrochloric acid, ammonia. 

Properties Red crystals. Volatile at high temperatures. D 4.768, mp 167C, bp 420C. Soluble in carbon disulfide, hydrochloric acid, and solution of potassium iodide insoluble in alcohol and chloroform ... 

Properties Colorless to light-yellow mobile nonpolar liquid of highly refractive nature aromatic odor. Bp 80.1C, fp 5.5C, d 0.8790 (20/4C), wt/gal 7.32 lb, refr index 1.50110 at 20C, flash p 12F (—11C) (CC), surface tension 29 dynes/cm autoign temp 1044F (562C). Miscible with alcohol, ether, acetone, carbon tetrachloride, carbon disulfide, acetic acid slightly soluble in water. Vapors burn with smoky flame. 

Available forms Solid elemental sulfur, sulfate in weak hydrochloric acid, barium sulfide in barium hydroxide solution, elemental sulfur in benzene solution, in tagged compounds such as carbon disulfide, chlorosulfonic acid, thiourea, sulfanilamide, thiamine, heparin, insulin, Sucaryl, etc. 

Properties Yellowish leaflets or glistening plates. Mp 90-91C, sublimes with decomposition, bp 390C. Insoluble in water soluble in benzene, ether, carbon disulfide, and acids. 

Under this heading are brought together the heterocyclic thioxo compounds which may be synthesized from an amine and carbon disulfide (dithiocarbamic acids) with a difunctional compound. Generally the dithiocarbamic acid (CLXXXVI) is prepared first and subsequently cyclized. However, this is not always necessary in several instances the desired heterocychc thioxo compound may be obtained from a mixture of the three reagents. These cyclization reactions are shown schematically in scheme t. 

Considering that the chemical reactivity of carboxylic acids is similar to that of carbonic acids, as is observed in amide and ester formation, we have attempted the substitution of carbon dioxide for carboxylic acids in the coupling reaction with amines by using phosphites in pyridine or imidazole, and found that ureas are in fact produced in good yields (Eq. (4))6. Similarly, carbon disulfide reacts with amines to yield the corresponding thioureas (Eq. (5)). 

The dithio derivative of carbonic acid is xanthogenic acid (1), unknown in the free state, the anhydride of which, carbon disulfide, is in itself an active substance with very good biological properties. 

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