Sciencemadness Discussion Board

What is the product of the following equations

khourygeo77 - 18-10-2017 at 10:52

Ethanol + Sulfuric acid ---> Diethyl ether? Any other possible product?

Ethanol + Acetic acid ----> Ethyl acetate? any other possible product??

Ethanol + Nitric acid ----> ???

Ethanol + HCL acid -----> Chloroethane? Any other possible product?

I heard somewhere that depending on the concentration of the acid, the product varies. Is this true?

Thanks


Sigmatropic - 18-10-2017 at 12:04

ethanol + sulfuric acid could form ethyl sulfuric acid, ethene, diethyl sulfate depending on exact conditions (temperature, concentration, presence of dehydrating agents)
ethanol + acetic acid forms ethyl acetate. Perhaps under forcing conditions one could obtain triethyl orthoacetate, although I doubt this.
ethanol + nitric acid could form ethyl nitrate or, perhaps under conditions I'm unawere of the result could be oxidation to acetaldehyde or acetic acid.
Ethanol + HCl could form ethyl chloride but some kink of lewis acid catalyst is needed.

Especially the ethanol + sulfuric acid system is well studied and depending on conditons various ratio's of ethene and diethyl ether are usually obtained.

[Edited on 18-10-2017 by Sigmatropic]

LearnedAmateur - 19-10-2017 at 08:49

Here are some of the temperatures required for the ethanol and sulphuric acid reactions:
<140C = ethyl sulphate (sulfovinic acid)
140 - 170C = diethyl ether
>170C = ethene

Some diethyl sulphate is produced in varying quantities through the reaction of ethanol, diethyl ether, or ethene with concentrated sulphuric acid, although this is usually minor and increases with temperature (easier removal of water), so the production of ethene will have the highest amount of DES as it reacts directly with H2SO4 with no water byproduct. Fuming sulphuric acid is typically used in the synthesis of diethyl sulphate from these reagents because of its dehydrating properties, and dessicants such Na2SO4 improve subsequent yields by driving the equilibrium to the product side.

Hydrochloric acid and ethanol do react although this is very slow (secondary and tertiary alcohols are progressively more reactive) to make chloroethane and water. Lucas' reagent is commonly employed to facilitate the reaction as opposed to just HCl, an equimolar solution of concentrated HCl and anhydrous ZnCl2, and the mixture is heated. The ZnCl2 is the Lewis acid that Sigmatropic suggested, which forms an adduct with the ethanol at the oxygen. ZnCl2OH is thus cleaved from the molecule and the ethyl carbocation is left to react with the chloride through SN1 addition, where the remaining H+ reacts with the Lewis adduct to form water and regenerate the ZnCl2 catalyst.

Can't really add anything else here except that fuming nitric acid is required to make EtONO2 by forcing the equilibrium by dehydration, and that ethyl acetate requires a strong acid catalyst in order to protonate the ethanol for removal. Probably gone a bit overboard with the explanations but information is always useful and might help you further your understanding of organic chemistry.

DraconicAcid - 19-10-2017 at 10:24

I'm pretty sure that if you heat nitric acid with ethanol, you will get oxidation.