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Sodium hydride is the chemical compound with the empirical formula Na H. This alkali metal hydride is primarily used as a strong yet combustible base in organic synthesis . NaH is a saline (salt-like) hydride , composed of Na + and H − ions, in contrast to molecular hydrides such as borane , silane , germane , ammonia , and methane .
Alcohol oxidation is a collection of oxidation reactions in organic chemistry that convert alcohols to aldehydes, ketones, carboxylic acids, and esters. The reaction mainly applies to primary and secondary alcohols. Secondary alcohols form ketones, while primary alcohols form aldehydes or carboxylic acids. [1] A variety of oxidants can be used.
With strong bases such as sodium hydride or sodium they form salts [a] called alkoxides, with the general formula RO − M + (where R is an alkyl and M is a metal). R−OH + NaH → R−O − Na + + H 2 2 R−OH + 2 Na → 2 R−O − Na + + H 2. The acidity of alcohols is strongly affected by solvation. In the gas phase, alcohols are more ...
The hydride adds to an electrophilic center, typically unsaturated carbon. Hydrides such as sodium hydride and potassium hydride are used as strong bases in organic synthesis. The hydride reacts with the weak Bronsted acid releasing H 2. Hydrides such as calcium hydride are used as desiccants, i.e. drying agents, to remove trace water from ...
Other alkali metals can be used in place of sodium, and most alcohols can be used in place of methanol. Generally, the alcohol is used in excess and left to be used as a solvent in the reaction. Thus, an alcoholic solution of the alkali alkoxide is used. Another similar reaction occurs when an alcohol is reacted with a metal hydride such as NaH.
Trimethyl borate is the main precursor to sodium borohydride by its reaction with sodium hydride in the Brown-Schlesinger process: 4 NaH + B(OCH 3) 3 → NaBH 4 + 3 NaOCH 3. It is a gaseous anti-oxidant in brazing and solder flux. Otherwise, trimethyl borate has no announced commercial applications.
Under ideal conditions the reaction produces 50% of both the alcohol and the carboxylic acid (it takes two aldehydes to produce one acid and one alcohol). [5] This can be economically viable if the products can be separated and both have a value; the commercial conversion of furfural into furfuryl alcohol and 2-furoic acid is an example of this ...
In practice, considerable sodium is consumed by the formation of hydrogen. [citation needed] For this reason, an excess of sodium is often required. Because the hydrolysis of sodium is rapid, not to mention dangerous, the Bouveault-Blanc reaction requires anhydrous ethanol and can give low yields with insufficiently dry ethanol.