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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.
Through a variety of mechanisms, the removal of a hydride equivalent converts a primary or secondary alcohol to an aldehyde or ketone, respectively. The oxidation of primary alcohols to carboxylic acids normally proceeds via the corresponding aldehyde, which is transformed via an aldehyde hydrate (gem-diol, R-CH(OH) 2) by reaction with water ...
In their handling properties, lithium aluminium hydride and sodium borohydride (and their derivatives) strongly differ. NaBH 4 is far easier to handle than LiAlH 4, being air stable for weeks. It can be used with water or ethanol as solvents, whereas LiAlH 4 reacts explosively with protic solvents.
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 ...
The term alcohol originally referred to the primary alcohol ethanol (ethyl alcohol), which is used as a drug and is the main alcohol present in alcoholic drinks. The suffix -ol appears in the International Union of Pure and Applied Chemistry (IUPAC) chemical name of all substances where the hydroxyl group is the functional group with the ...
The k' pathway implicates a reaction between the doubly charged anion (RCHO 2 2−) and the aldehyde. The direct transfer of hydride ion is evident from the observation that the recovered alcohol does not contain any deuterium attached to the α-carbon when the reaction is performed in the presence of D 2 O.
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.
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.