Methane acetic acid

An interesting example of the role of solvent in determining the conformation of the linear precursor and hence the relative stereochemistry in the product is provided by the thiamorpholine derivative (7) (90JHC1661). Deprotection of this by catalytic hydrogenolysis leads to cyclization yielding a mixture of (8) and (9). The product ratio depends on the solvent used for the hydrogenolysis. In methanol it is 35 54, whereas in dichloro-methane-acetic acid (20 1) the ratio is 56 9. Obviously the rotamer populations are influenced by the solvent chosen. 

The first set of aliphatic compounds included methane, acetic acid, 2-butanone, and acetamide, which were analyzed using EHOMO as the molecular descriptor. The relationship between the kinetic rates of these compounds and EHomo reflected a very good correlation (r2 = 0.96). Figure 10.14 shows the correlation of the set of aliphatic compounds. From this figure, it can be seen that the kinetic rate decreases as the EHOMO increases. Application of the F test showed that the level of significance was 2.5%. That is, there is a 2.5% chance of erroneously concluding that they are not related. Based on Table 10.12, the calculated F(12) was 40.5, which is larger than the F(u)a0 025... 

Surprisingly, CaCl2 was also found to be effective in the carboxylation of alkanes such as ethane, propane, and cycloalkanes by CO in the presence of K2S208 and TFA [6, 7]. With methane acetic acid was formed almost quantitatively by using CaCl2 as catalyst, although a long reaction time (140 h) was required [7]. In TFA, methane and CO could be converted to acetic acid by the catalytic system... 

Methane, acetic acid, acetaldehyde, and ethanol constitute approximately 90 carbon atom percent of the primary products from the hydrogenation of CO over Rh/SiO and Rhr-Mn/SiOi catalysts at 250 -300°C and 30-200 atm pressure in a back-mixed reactor with H /CO = 1. The rate of reaction and the ratio, CHj /C chemicals, vary with (Pjy / The addition of 1% Mn raises the synthesis rate of a 2.5% Rh/SiOfi catalyst about tenfold. The kinetics and the product distribution are consistent with a mechanism in which CO is adsorbed both associatively and dissodatively. The surface carbon produced by the dissociative CO chemisorption is hydrogenated through a Rh-CHs intermediate, and CO insertion in that intermediate results in formation of surface acetyl groups. 

Whereas androstane, cholestane and androstanones can be oxidized in dichloro-methane/acetic acid and even in methanol (see Section II.A.5) the 3- and 17-acetoxy-androstanes as well as 3,17-diacetoxyandrostane resist CH oxidation in this solvent. 5a-Cholestan-3j5-yl acetate is converted in dichloromethane/acetic acid in low yield (5-10%) to tetratrifluoroacetoxy-5a-cholestane-3jS-yl acetate. The side chain at C(i7) is not split off to a noticeable extent. 

The selected eluents for sihca gel are chloroform-ethyl acetate-formic acid (5 4 1), n-hexane-ethyl acetate-formic acid (15 9 2), chloroform-acetic acid-water (2 1 1), toluene-dichloromethane-formic acid (40 50 10), and dichloro-methane-acetic acid-water (100 50 50, lower phase). 

Methane-acetic acid conversion via direct catalytic conversion ... 

Column 250 x 4.6 5 xm silica (Perkin Elmer) (Before use, wash column with dichloro-methane acetic acid 95 5.)... 

Methane Acetic acid Glycol aldehyde Ethylene glycoP Acetaldehyde Ethanol Ethylene Hydroxyacetone Acetone ... 

Figure 14.8a shows a simplified flowsheet for the manufacture of acetic anhydride as presented by Jeffries. Acetone feed is cracked in a furnace to ketene and the byproduct methane. The methane is used as furnace fuel. A second reactor forms acetic anhydride by the reaction between ketene from the first reaction and acetic acid. 

Without carbon, the basis for life would be impossible. While it has been thought that silicon might take the place of carbon in forming a host of similar compounds, it is now not possible to form stable compounds with very long chains of silicon atoms. The atmosphere of Mars contains 96.2% CO2. Some of the most important compounds of carbon are carbon dioxide (CO2), carbon monoxide (CO), carbon disulfide (CS2), chloroform (CHCb), carbon tetrachloride (CCk), methane (CHr), ethylene (C2H4), acetylene (C2H2), benzene (CeHe), acetic acid (CHsCOOH), and their derivatives. 

Although turnover of the catalyst is low, even unreactive cyclohexane[526] and its derivatives are oxidatively carbonylated to cyclohexanecarboxylic acid using KiS Og as a reoxidant in 565% yield based on Pd(II)[527]. Similarly, methane and propane are converted into acetic acid in 1520% yield based on Pd(II) and butyric acid in 5500% yield [528],... 

Addition occurs rapidly in a variety of solvents including pentane benzene dichloro methane chloroform and acetic acid... 

Decomposition Reactions. Minute traces of acetic anhydride are formed when very dry acetic acid is distilled. Without a catalyst, equiUbrium is reached after about 7 h of boiling, but a trace of acid catalyst produces equiUbrium in 20 min. At equiUbrium, about 4.2 mmol of anhydride is present per bter of acetic acid, even at temperatures as low as 80°C (17). Thermolysis of acetic acid occurs at 442°C and 101.3 kPa (1 atm), leading by parallel pathways to methane [72-82-8] and carbon dioxide [124-38-9] and to ketene [463-51-4] and water (18). Both reactions have great industrial significance. 

The materials of constmction of the radiant coil are highly heat-resistant steel alloys, such as Sicromal containing 25% Cr, 20% Ni, and 2% Si. Triethyi phosphate [78-40-0] catalyst is injected into the acetic acid vapor. Ammonia [7664-41-7] is added to the gas mixture leaving the furnace to neutralize the catalyst and thus prevent ketene and water from recombining. The cmde ketene obtained from this process contains water, acetic acid, acetic anhydride, and 7 vol % other gases (mainly carbon monoxide [630-08-0][124-38-9] ethylene /74-< 3 -/7, and methane /74-< 2-<7/). The gas mixture is chilled to less than 100°C to remove water, unconverted acetic acid, and the acetic anhydride formed as a Hquid phase (52,53). 

Bis(2,4,6-trinitrophenyl)methane when treated with NaAc in acetic acid produced (580) as a thermostable explosive (80MIP41600). The conversion of o-nitrotoluene into 2,1-benzisoxazole was effected by mercury(II) oxide catalysis. A mercury containing intermediate was isolated and was demonstrated to be converted into 2,1-benzisoxazole (67AHC(8)277). The treatment of o-nitrotoluene derivative (581) with sulfuric acid gave (582) in 35% yield (72MI41607). 

Ferrocene (46.4 g., 0.250 mole) (Note 1) is added to a well-stirred solution of 43.2 g. (0.422 mole) of bis(dimethylamino)-methane (Note 2) and 43.2 g. of phosphoric acid in 400 ml. of acetic acid in a 2-1. three-necked round-bottomed flask equipped with a condenser, a nitrogen inlet, and a mechanical stirrer (Note 3). The resulting suspension is heated on a steam bath under a slow stream of nitrogen (Note 4) for 5 hours (Note 5). The reaction mixture, a dark-amber solution, is allowed to cool to room temperature and is diluted with 550 ml. of water. The unreacted ferrocene is removed by extracting the solution with three 325-ml. jiortions of ether. The aqueous solution is then looled in ice water and made alkaline by the addition of 245 g. 

A rhodium-on-alumina catalyst deactivated in bis-(4-aminophenyl)-methane saturation (I IS C, 100 psig) was regenerated by two washings with aqueous ammonia at 65°C, followed by drying at 90°C(I6) or by washing with acetic acid. 

Preparation of 4,4 -Dioxy-Diphenyl-(2-Pyridyl)-Methane 100 g of 3,3 -dichloro-4,4 -dioxy-diphenyl-(2-pyridyl)-methane, obtained as above described, are dissolved in 660 ml of 10% sodium hydroxide and 49 g of Raney-nickel alloy are added to the solution with vigorous stirring, at room temperature and during 4 hours. The mixture is stirred overnight at room temperature, then it is filtered and brought to pH 5 with 10% acetic acid. The precipitate obtained, filtered, washed and dried is then dissolved in 1,500 ml of 95°C boiling alcohol to eliminate the insoluble salts. The residue obtained after the evaporation of the alcoholic solution weighs 74 g (yield 92%). The yield in respect to 2-pyridinaldehyde is 63.5%. 

The decanted aqueous phase was extracted three times with a total of 150 ml of ethyl acetate. The combined organic solutions were filtered over Clarcel and extracted three times with a total of 150 ml of an Iced normal aqueous methane-sulfonic acid solution. The combined acid extracts were rendered alkaline on an ice bath with 30 ml of ION caustic soda solution. The separated oil was extracted four times with a total of 200 ml of ether. The combined ethereal extracts were washed twelve times with a totai of 360 ml of distilled water, dried over anhydrous magnesium sulfate in the presence of 0.3 g of animal charcoal and evaporated under reduced pressure on a water bath at 40°C. The oily residue obtained (3.8 g) was dissolved in 30 ml of boiling acetonitrile. After cooling for 2 hours at 3°C, the crystals formed were separated, washed with 5 ml of acetonitrile and dried at ambient temperature at low pressure. 

---