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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.
To selectively form the allyl alcohol and avoid the 1,4 product, the Luche reduction uses "cerium borohydride" generated in situ from NaBH 4 and CeCl 3 (H 2 O) 7 [21] [22] The hydride source Zn(BH 4) 2 also shows 1,2 selectivity, as well as greater diastereoselectivity.
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 ...
Organocatalytic transfer hydrogenation has been described by the group of List in 2004 in a system with a Hantzsch ester as hydride donor and an amine catalyst: [12] In this particular reaction the substrate is an α,β-unsaturated carbonyl compound. The proton donor is oxidized to the pyridine form and resembles the biochemically relevant ...
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.
In the transition state for hydride transfer (II → III), the large substituent of the ketone is aligned inward to avoid steric interactions with the outward-pointing R group of the oxazaborolidine, which is often tethered to the nitrogen atom. After hydride transfer, complex III releases the product and coordinates a second molecule of borane ...
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.
Common hydrides used are sodium hydride and potassium hydride. The hydride forms hydrogen gas with the liberated proton from the other molecule. The hydrogen is dangerous and could ignite with the oxygen in the air, so the chemical procedure should be done in an inert atmosphere (e.g., nitrogen). Deprotonation can be an important step in a ...