High chemistry problems, about esterification reactions

Ethanol concentrated sulphuric acid glacial acetic acid.

Concentrated sulfuric acid is denser than ethanol, and if concentrated sulfuric acid is added first, ethanol will only float on it, and a large amount of exothermic liquid will splash, and the ethanol will also evaporate.

Careful heating: easy to burst boiling, often add broken porcelain to prevent bursting.

Long condensation reflux.

Extraction of ethyl acetate: pass into saturated sodium carbonate solution.

There is no diagram anyway, that catheter can't touch the liquid level, otherwise it will gasp.

I'm dizzy... It's not filtration, it's dispensing.

I'm dizzy, that test tube doesn't affect you at all, if you want to be bigger, if you want less, you can be smaller.

Ethanol, concentrated sulfuric acid, glacial acetic acid can be abbreviated as "alcohol, sulfuric acid", homonym, pure sulfuric acid, which is easier to remember.

Ethanol is less dense than concentrated sulfuric acid, and if you add concentrated sulfuric acid and ethanol first, and just float on it, the liquid will splash and burn people, and the ethanol will evaporate.

Prevent boiling, because concentrated sulfuric acid can hurt people if it is ejected.

Short prevents gasping.

with saturated sodium carbonate solution.

Saturated sodium carbonate solution has three effects.

1 Dissolve the volatile ethanol.

2. Reduce the solubility of ethyl acetate.

3. Neutralize volatile acetic acid.

First of all, the first question is the same as concentrated sulfuric acid + water, it is necessary to add concentrated sulfuric acid to ethanol and glacial acetic acid, because concentrated sulfuric acid is dissolved and exothermic, and it is easy to cause sulfuric acid to splash out if it is acid first and then water.

2 Heat carefully Mainly because ethanol is volatile, 3 not impressive.

4, with a saturated sodium bicarbonate solution. Volatile acids and absorbed ethanol can be removed, and the solubility of ethyl acetate can also be reduced.

CH3COOH + CH3CH2OH = Reversible = CH3COOCH2CH3 + H2O (Poor Condition: Concentrated Sulfuric Acid, Heating).

The rest of the esterification reactions are the same as this reaction: acid dehydroxyl alcohol dehydrogenation (acids include organic acids and inorganic oxygenated acids).

For example: Cave ch3ch2oh + hno3 = reversible = ch3ch2ono2 + h2o (conditions: concentrated sulfuric acid, heating).

1. The conditions of the conventional esterification reaction are concentrated sulfuric acid, heating, and concentrated sulfuric acid as a water absorbent and catalyst.

2. The esterification reaction is generally a reversible reaction. The traditional esterification technique is to heat the reflux reaction with acid and alcohol catalyzed by acid (usually concentrated sulfuric acid). This reaction is also called Fischer esterification.

The role of concentrated sulfuric acid is a catalyst and water absorbent, which can protonize the carbonyl group of carboxylic acid, enhance the electrophilicity of carbonyl carbon, and accelerate the reaction rate; It is also possible to remove water, a by-product of the reaction, and improve the yield of esters.

3. If the raw materials are low-grade carboxylic acids and alcohols, which are soluble in water, water can be added to the reaction solution after the reaction (saturated sodium carbonate solution can be added if necessary), and the reaction solution is placed in the separating funnel for separating treatment, and the upper ester layer that is insoluble in water is collected, so as to purify the ester generated by the reaction. The function of sodium carbonate is to react with carboxylic acid to form carboxylate, increase the solubility of carboxylic acid, and reduce the solubility of esters. If the boiling point of the product ester is low, the ester can also be continuously evaporated during the reaction to shift the reaction equilibrium to the right and condense to collect the volatile ester.

4. However, there are also a few esterification reactions, in which the hydroxyl proton of acid or alcohol is protonated, and water is removed to generate acyl cation or carbocation intermediates, which then react with alcohol or acid to form esters. These reactions do not follow the rule of "acid out of hydroxyl alcohol out of hydrogen".

5. Carboxylic acids are reacted with alcohols to form esters after acid chloride. Acid chloride is more reactive than carboxylic acids, so this method is a common method for ester preparation, and the yield is generally higher than direct esterification. For less reactive acyl halides and alcohols, a small amount of base, such as sodium hydroxide or pyridine, can be added.

H3C-CoCl + Ho-CH2-CH3 H3C-Coo-CH2-CH3 + H-Cl carboxylic acid is reacted with alcohol to form an ester by anhydride. Carboxylic acids are then reacted with halogenated hydrocarbons to form esters through carboxylates. The reaction mechanism is the nucleophilic substitution of carboxylate anion on halogenated hydrocarbon-carbon.

1. Conditions: Esterification reaction is a kind of organic chemical reaction, which is the reaction of alcohol and carboxylic acid or oxygenated inorganic acid to form ester and water.

2. Generally, it is normal temperature or heating conditions and adding catalysts.

3. The two compounds form esters (the typical reaction is the reaction of acid and alcohol to form esters), which is called esterification reaction.

4. There are two situations: carboxylic acid reaction with alcohol and inorganic oxygenated acid reaction with alcohol.

5. The reaction process between carboxylic acid and alcohol is generally as follows: the hydroxyl group in the carboxylic acid molecule and the hydrogen atom of the hydroxyl group in the alcohol molecule are combined into water, and the rest of the parts are combined with each other to form esters. This has been confirmed with tracer atoms.

6. Formula: acid dehydroxyl alcohol dehydrogenation (acid dehydroxyl alcohol dehydrogenation). The esterification reaction of carboxylic acid and alcohol is reversible, and the reaction is generally very slow, so concentrated sulfuric acid is often used as a catalyst. Polycarboxylic acids react with alcohols to form a variety of esters.

7. Esterification reaction is a reversible reaction, under normal circumstances, the reaction is not complete, according to the principle of reaction equilibrium, to improve the yield of esters, it is necessary to separate a component from the product or make one of the reactants excessive, so that the reaction is carried out in the positive direction.

8. The esterification reaction is a single-line two-way reaction.

Esterification: Alcohol reacts with carboxylic acids (can also be inorganic acids) to form esters, which are characterized by the production of 1 molecule of water. The most common reaction is the reaction of ethanol with acetic acid to form ethyl acetate.

Addition reaction: mainly for the breaking of unsaturated bonds, C=C or C triple-C bonds, double bonds, then 2 atoms or groups are added on top. The most common reaction is the reaction of ethylene with bromine water to form dibromoethane.

Substitution reaction: It may seem complicated to say that any one atom or group in an organic compound molecule is replaced by another atom or group of the same type in a reagent. It can be simply thought of knocking out an atom (or functional group) on an organic compound and replacing it with another atom or group in the place where it was knocked out.

A common reaction is the reaction of methane with chlorine to form a substitute.

By definition, you will certainly find that esterification reactions are substitution reactions.

Esterification is a type of substitution reaction, and addition reaction is a reaction in which a carbon-carbon double bond or a carbon-carbon triple bond binds to other molecules.

Lipid reaction:

Reaction format: rcooh+r'oh→rcoor'+H2O Catalyst: Concentrated dehydrated acid or anhydride Reaction substance: Acid dehydroxyl alcohol dehydrogenation. Because the carboxyl group is easy to lose hydrogen and difficult to dehydroxate, an acid catalyst is used.

CH3COOH+CH3CH2OH = Reversible = CH3COOCH2CH3 + H2O (Conditions: concentrated sulfuric acid, heating).

The rest of the esterification reactions are the same as this one: acid dehydroxyl alcohol dehydrogenation (acids include organic acids and inorganic oxygenated acids).

For example: CH3CH2OH+HNO3=Reversible=CH3CH2ONo2+H2O (conditions: concentrated sulfuric acid, heating).

It is sufficient to grasp the esterification reaction of acetic acid and ethanol. Acids and alcohols are reflected to form esters and water. Acid dehydroxyl alcohol dehydrogenation.

Reaction conditions: concentrated sulfuric acid, heating.