Formic acid, sodium salt

Formic acid propyl ester. See Propyl formate Formic acid sodium salt. See Sodium formate Formic aldehyde. See Formaldehyde Formic ether. See Ethyl formate Formimidic acid, 1-carbamoyl-. SeeOxamide Formol 55. See Urea-formaldehyde resin Formol. See Formaldehyde Formonitrile. See Hydrogen cyanide Formosa camphor. See Camphor Formosa camphor oil Formose oil of campor. See Camphor (Cinnamomum camphora) oil Formosol. See Sodium formaldehyde sulfoxylate... 

While it is cooling down, the underground chemist gets ready for the next step in the process. He is going to recover the unused methylamine for use in the next batch. This cuts his consumption of methylamine to about half of what it would be without this technique. What he is going to do is react the unused N-methylformamide with a strong solution of sodium hydroxide. The N-methylformamide is hydrolyzed to form methylamine gas and the sodium salt of formic acid (sodium formate). In chemical writing, this reaction is as follows ... 

We observe that on increasing the total salt concentration from 0.01 to 0.1 mole 1 there is about 35% increase in rate due to increased ionimtion of the formic acid (secondary salt effect) and an increase of about 10% due to the primary salt effect. The last four results in the table show that the primary salt effect is similar in sodium chloride and sodium acetate solutions. 

Formaldehyde sodium bisulfite adduct Formaldehyde sodium sulfoxylate. See Sodium formaldehyde sulfoxylate Formal glycol. See 1,3-Dioxolane Formalin. See Formaldehyde Formamide, 1,1 -azobis-. See Azodicarbonamide Formic acid, aluminum salt. See Aluminum formate Formic aldehyde Formol. See Formaldehyde p-FormyInitrobenzene. See p-Nitrobenzaldehyde Fossil flour. See Diatomaceous earth Silica, fumed Fossil wax. See Ozokerite Franklin. See Calcium carbonate Free crystalline silica. See Quartz Freon 113. See Trichlorotrifluoroethane P-D-Fructofuranosyl-a-D-glucopyranoside. See Sucrose P-D-Fructofuranosyl-a-D-glucopyranoside benzoate. See Sucrose benzoate P-D-Fructofuranosyl-a-D-glucopyranoside monohexadecanoate. See Sucrose palmitate... 

Ethyl formate. Reflux a mixture of 61 g. (50 ml.) of A.R. formic acid (98/100 per cent.) and 31 g. (39-5 ml.) of absolute ethyl alcohol for 24 hours. Transfer to a Claisen flask with fractionating side arm (or attach a fractionating column to the flask), distil and collect the liquid passing over below 62°. Wash the distillate with saturated sodium bicarbonate solution and saturate with salt before removing the ester layer. Dry with anhydrous sodium or magnesium sulphate, filter, and distil. The ethyl formate passes over at 53-54°. The yield is 36 g. 

The reaction of formate salts with mineral acids such as sulfuric acid is the oldest iadustrial process for the production of formic acid, and it stiU has importance ia the 1990s. Sodium formate [141-53-7] and calcium formate [544-17-2] are available iadustriaHy from the production of pentaerythritol and other polyhydric alcohols and of disodium dithionite (23). The acidolysis is technically straightforward, but the unavoidable production of sodium sulfate is a clear disadvantage of this route. 

Improvements to the methanol reductant processes may be found in the patent Hterature. These include methods of operation to reduce acidity in the crystallisation 2one of the generator to promote crystallisation of sodium sulfate and to reduce sulfuric acid consumption (48). Other improvements sought are the elimination of formic acid and chlorine impurities from the chlorine dioxide, as weU as methods of recovering acid and sodium hydroxide, or acid and neutral sodium sulfate from the soHd sodium sesquisulfate salt waste stream (48—52). 

Acids that are solids can be purified in this way, except that distillation is replaced by repeated crystallisation (preferable from at least two different solvents such as water, alcohol or aqueous alcohol, toluene, toluene/petroleum ether or acetic acid.) Water-insoluble acids can be partially purified by dissolution in N sodium hydroxide solution and precipitation with dilute mineral acid. If the acid is required to be free from sodium ions, then it is better to dissolve the acid in hot N ammonia, heat to ca 80°, adding slightly more than an equal volume of N formic acid and allowing to cool slowly for crystallisation. Any ammonia, formic acid or ammonium formate that adhere to the acid are removed when the acid is dried in a vacuum — they are volatile. The separation and purification of naturally occurring fatty acids, based on distillation, salt solubility and low temperature crystallisation, are described by K.S.Markley (Ed.), Fatty Acids, 2nd Edn, part 3, Chap. 20, Interscience, New York, 1964. 

The reduction of the double bond of an enamine is normally carried out either by catalytic hydrogenation (MS) or by reduction with formic acid (see Section V.H) or sodium borohydride 146,147), both of which involve initial protonation to form the iminium ion followed by hydride addition. Lithium aluminum hydride reduces iminium salts (see Chapter 5), but it does not react with free enamines except when unusual enamines are involved 148). 

The reduction of iminium salts can be achieved by a variety of methods. Some of the methods have been studied primarily on quaternary salts of aromatic bases, but the results can be extrapolated to simple iminium salts in most cases. The reagents available for reduction of iminium salts are sodium amalgam (52), sodium hydrosulfite (5i), potassium borohydride (54,55), sodium borohydride (56,57), lithium aluminum hydride (5 ), formic acid (59-63), H, and platinum oxide (47). The scope and mechanism of reduction of nitrogen heterocycles with complex metal hydrides has been recently reviewed (5,64), and will be presented here only briefly. 

Dihydro- and 1,4-dihydro derivatives are formed as intermediates in the reduction of quaternary pyridine salts and their homologues with sodium borohydride or formic acid. A proton is added to the present enamine grouping and the formed immonium salts are reduced to the l-methyl-l,2,5,6-tetrahydropyridine derivatives (157) and to completely saturated compounds (158) (254) (Scheme 14). 

Reduction of the quaternary immonium salt 161, obtained by treatment of l-methyl-2-ethylidenepyrrolidine with ethyl bromoacetate, by means of either sodium borohydride or formic acid, leads to (—)-erythro-2-(2-N-methylpyrrolidyl)butyric acid (162), in agreement with Cram s rule (196). 

The pH at the stoichiometric point depends on the type of salt produced in the neutralization reaction. At the stoichiometric point of the titration of formic acid, HCOOH, with sodium hydroxide,... 

SOLUTION The salt present at the stoichiometric point, sodium formate, provides basic formate ions, and so we expect pH > 7. From Table 10.1, Ka = 1.8 X 10 4 for formic acid therefore, Kb = KJKa = 5.6 X 1CT11. 

A mixture containing 15.7% of sodium borohydride in DMF decomposed when it was heated by forming trimethylamine. The temperature of the solid residue formed rose to 310°C. This interaction occurs after a period of induction, which depends on temperature (45 hours at 62°C 45 minutes at 90°C). This period is reduced, if formic acid is present because of the formation of the F320 salt (according to the authors). 

Buffers are necessary to adjust and maintain the pH. Buffering agents can be salts of a weak acid and a weak base. Examples are ammonium, potassium, sodium carbonates (caustic soda), bicarbonates, and hydrogen phosphates [1345]. Weak acids such as formic acid, fumaric acid, and sulfamic acid also are recommended. Common aqueous buffer ingredients are shown in Table 17-8. 

When Fast Colour Salts are used hydrochloric acid and sodium nitrite are obviously not required, although some Fast Colour Salts do need an addition of acetic or formic acid. The nonionic dispersing agent is still necessary but as most Fast Colour Salts contain an alkali-... 

Oxidation of one molar proportion with sodium pieriodate produces two equivalents of formic acid, in accordance with the existence of hydroxyl groups attached to four contiguous carbon atoms. This oxidation (and also that carried out with lead tetraacetate) gives an aldehyde, whose semicar-bazone has an analysis corresponding to that of the semicarbazone of an ethyl formyl-methyl-furoate (XII). By oxidation of aldehyde XII with silver oxide in alkaline solution, 2-methyl-3,4-furandicarboxylic acid (XIV) was obtained this was identical with the compound described by Alder and Rickert.20 The identity was confirmed by preparation of the respective dianilides. The acid XIV has also been prepared by the reaction between the sodium salt of ethyl acetoacetate and ethyl bromopyruvate.9... 

When the soluble salt sodium formate (NaHCOO) is added to a formic acid solution, the salt undergoes complete dissociation in water to produce the common ion, HCOO-. The original equilibrium involving the weak acid shifts to the left. As a result, the fraction of HCOOH molecules that undergo ionization in aqueous solution will be less. 

Other salts of formic acid have been used with good results. For example, sodium and preferably potassium formate salts have been used in a water/organic biphasic system [36, 52], or with the water-soluble catalysts discussed above. The aqueous system makes the pH much easier to control minimal COz is generated during the reaction as it is trapped as bicarbonate, and often better reaction rates are observed. The use of hydrazinium monoformate salts as hydrogen donors with heterogeneous catalysts has also been reported [53]. 

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