Hydrogenation acetals

E 262 Sodium acetates (i) Sodium acetate (ii) Sodium hydrogen acetate (sodium diacetate)... 

Sodium hydrogen acetate (diacetate) Sodium hydrogen carbonate Sodium hydrogen (bi) sulphite... 

Seaetms.—1. By the action of reducing or hydrogenating agents, as zinc and hydrochlorio acid, sulphuretted hydrogen, acetic acid and iron, or potassic acsenite, nitrobenzol is con verted into aniline —... 

ACETIC ACID HC,H,0, HYDROGEN ACETATE NoC,H,0,SODIUM ACETATE... 

Fig. 1. Hydrogen production by C. saccharolyticus using (A) glucose medium (B) xylose medium and (C) glucose and xylose medium. (—O—), Hydrogen (— —), acetate (—x—), lactate (— —), glucose (— —), xylose (—O—), OD580nm.

The semi-hydrogenated acetate coupled product was dissolved in a 1% solution of sodium hydroxide in methyl alcohol. The solution was allowed to stand about 12 hours at room temperature under a blanket of nitrogen. The hydrolysis was complete as shown by the total absence of ester bands in an infrared analysis. 

Hydrogen Acetate+C02 Acetate+C02 Succinate Succinate Propionate +ATP Lipids +ATP... 

Figure 15.2. Effect of the molar ratio of acetate to the sum of acetate and butyrate on the yields of biomass, hydrogen, acetate, and butyrate to glucose. Source Adopted from Chen et al., 2006b.

An alternative, new approach for the synthesis of co-carboxamide-containing amino acid derivatives is based on the oxidation of suitably protected a,a-diamino acids (2,4-diamino-butyric acid, ornithine, lysine) with permanganatet or ruthenium(lV) oxide,as shown in Scheme 6. The co-Boc-carboxamide group is stable toward catalytic hydrogenation, acetic acid, and 10% TEA/CH2CI2, is unstable in the presence of 1M NaOH/MeOH, and is cleaved with methanolic hydrazine hydrate, 25% TFA/CH2CI2, 25% HBr/AcOH, or HF.P l... 

King G. M. (1984) Utilization of hydrogen, acetate, and noncompetitive substrates by methanogenic bacteria in marine sediments. Geomicrobiol. J. 3, 275-306. 

Sprensen K. B., Finster K., and Ramsing N. B. (2001) Thermodynamic and kinetic requirements in anaerobic methane oxidizing consortia exclude hydrogen, acetate, and methanol as possible electron shuttles. Microbial. Ecol. 42, 1-10. 

The relationship of the acid and methane phases to the scheme in Fig. 12.1 raises several interesting questions, such as where the acetogenic bacteria are located and whether methane is formed exclusively from acetate or from both carbon dioxide reduction and acetate in the methane-phase reactor. The experimental data useful in answering these questions include the observations that for a glucose-fed, two-phase digestion system, more than 96% of the products from the acid-phase reactor were carbon dioxide, hydrogen, acetate. 

To obtain ordinary commercial acetic add, acetate of lime is mixed with calcium chloride in proper proportions, and the solution concentrated until it crystallizes. The mother liquid is poured off and concentrated with the production of a second crop of crjstals this is repeated Until about four crops have been obtained. The crystals are then dissolved in water, filtered through animal charcoal mixed with about 10 per cent, of calcium chloride and recr . S callized. The crystals are distilled with a mixture of T part sulphuric acid of specific gravity i S4 and 2 parts water, and the resulting acetic acid concentrated. This acid should contain 33 per cent, by weight of hydrogen acetate. 

In the second example27 the fungus Geotrichum candidum is used and (5)-2-methyl-y-bu-tyrolactone is directly obtained from ( )-3-(l,3-dioxolan-2-yl)-2-buten-l-ol after stereospecific double bond hydrogenation, acetal hydrolysis and aldehyde oxidation followed by spontaneous cyclization. It is interesting to note that the aldehyde is oxidized in this reaction. 

There are four steps in these reactions as exemplified in the oxidative addition of acetic acid (1) to an alkene and the oxidative cyclization of 7b (Scheme 2). The first, rate-determining step is the slow reaction of acetic acid 1 or y9-keto ester 7b with Mn(OAc)3 to give Mn(III) enolates 2 and 8b, respectively [12, 13]. The rate of proton loss is proportional to the acidity of the hydrogen. Acetic acid, pK = 25,... 

Main staring materials Pyrocatechol, pyruvic acid, and ammonia Vanillin, hydantoin, hydrogen, acetic acid anhydride... 

Acetic acid—Acetyl hydrate—Hydrogen acetate—Pyroligneous acid—Acidum aceticum (TJ. S. Br.)—CEa,COOH—60. 

Copper(II) azide, an extremely sensitive explosive material, can be crystallized in the orthorhombic form by diffusing together solutions of CUSO4 and NaN3(5) in a solution of 1% hydrogen acetate in water [30]. Only small needle-shaped crystals have been grown by this technique. It should be mentioned that excess azide concentration in this solution must be avoided as the azide will form a soluble complex with copper ... 

Synonyms Glycerides, cottonseed-oil, mono-, hydrogenated, acetates Definition Acetyl ester of the monoglyceride derived from hydrogenated... 

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