How does a hydroxyl group become a carboxyl group and how do amino and carboxyl groups combine?

Primary and secondary alcohols can be hydrolyzed by bromination and cyano, or made into Grignard reagent and then attacked carbon dioxide.

Carboxyl group (English name: carboxyl) is the basic acid group in organic chemistry, all organic acids can be called carboxylic acids, composed of one carbon atom, two oxygen atoms and one hydrogen atom, the chemical formula -COOH. Hydrogen on the carboxyl group has a greater tendency to ionize, which makes the carboxylic acid acidic in aqueous solution.

The conjugated structure of carboxylate anion can be regarded as the potential driving force for easy ionization of hydrogen. The carbonyl group in the carboxyl group.

Under the influence of the hydroxyl group, it becomes very inactive, and does not react with nucleophiles such as HCN and NaHSO3, and its hydroxyl group is easier to dissociate than the alcohol hydroxyl group, showing weak acidity. Anions in carboxylates.

, bond averaging occurs due to the delocalization of electrons. Hence its two carbon-oxygen bonds are actually exactly equal.

When it reacts with oxygen, it first becomes an aldehyde group, and then it reacts with oxygen to become a carboxyl group.

Conversion of hydroxyl aldehyde group carboxyl group.

RCHH2OH RCHO RCOOH (oxidation reaction).

Hydroxyl group into carboxyl group plus potassium permanganate and other strong oxidants, carboxyl group to hydroxyl group plus lithium tetrahydro aluminum, carboxyl group to aldehyde lithium monohydrogen aluminium or (hydrogen, PD-baso4, sulfur-quinoline).

Yes, the carboxyl group is made up of hydroxyl and carbonyl groups.

But generally speaking, if there is a functional group of a carboxyl group, we can only say that there is a carboxyl group, but we cannot say that there is a hydroxyl group, a carbonyl group.

The way amino acid molecules combine is to link the hydroxyl group (-COOH) of one amino acid molecule and the amino group (-NH2) of another amino acid molecule, and at the same time remove a molecule of water, this combination method is called dehydration condensation.

Amino dehydrogenation, carboxyl dehydroxy.

There are many methods, and different methods can be taken according to the structure of carboxylic acids.

Introducing several common ones.

Acetic acid. First and ethanol.

Esterification produces ethyl acetate, then clessen ester condensation occurs under the action of strong bases such as sodium alkoxide, and acidification is obtained to obtain ethyl acetoacetate, and finally ethyl acetoacetate is used in sodium hydroxide.

Heated and decarboxylated in aqueous solution to obtain ethanol and acetone.

In this way, the carboxyl group in acetic acid is converted into the ketone carbonyl group in acetone.

There are 6 or 7 carbon diacids on the backbone (the carboxyl group is on the carbon at the end of the backbone), for example, adipic acid, heptanedic acid.

Such a diacid heating undergoes decarboxylation, dehydration, and the acquisition of five- or six-membered cyclic ketones. There are other alkanes on the backbone.

There are substituents on the ketone ring obtained when the base is obtained.

Adipic acid is heated to give cyclopentanone, and heptanetic acid is heated to give cyclohexanone.

Direct synthesis by acid chloride and organolithium reagents.

Carboxylic acid with thionyl chloride.

Phosphorus pentachloride and phosphorus trichloride are converted into acyl chloride, and then the acyl chloride reacts with organolithium reagents (including methyl lithium, lithium dihydrocarbonyl copper, n-butyllithium, phenyl lithium, etc.) to obtain ketones.

By reaction of carboxylic esters with an equal molar amount of Grignard reagent.

Ketones can be obtained by converting carboxylic acids into carboxylic acids, which are then reacted with an equal molar amount of Grignard reagent and hydrolyzed. Note that there should not be too much Grignard reagent, otherwise tertiary alcohol will be obtained.

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1. The hydroxyl group can be oxidized to an aldehyde group at the end of the chain, or it is remembered that the carbon connected to the hydroxyl group must contain 2 hydrogenocelery.

In the case of the hydroxyl group, the hydroxyl group can be oxidized to the aldehyde group.

2. If the carbon attached to the hydroxyl group contains 1 hydrogen atom, it can only be oxidized to a carbonyl group.

It cannot be changed to an aldehyde group.

3. If there is no hydrogen atom on the carbon attached to the hydroxyl group, catalytic oxidation cannot occur and it cannot be changed into an aldehyde group.

Carboxylic acids and organohalides are directly synthesized into ketocelery compounds.

Ketones play an important role in organic chemistry and are widely found in natural products, drugs, and dyes.

spices, etc. At the same time, it is also involved in various organic reactions, such as mannich reaction.

Wittig reaction, Grignard reaction, Passerini reaction, Baeyer Villiger oxidation reaction, etc.

The hydroxyl group (also known as the hydroxide group) is a common polar group. Hydroxyl groups mainly include alcohol hydroxyl groups, phenolic hydroxyl groups, etc.

Chemical reaction. 1.Reducible, can be oxidized to aldehydes or ketones or carboxylic acids.

2.Weakly acidic, phenolic hydroxyl reacts with sodium hydroxide to form sodium phenol. Although acidic, many aqueous solutions containing hydroxyl organic compounds are less acidic than water. Such as methanol (CH3OH), ethanol (CH3CH2OH), etc.

3.Elimination reactions can occur, such as the dehydration of ethanol to produce ethylene.

4.A displacement reaction can occur, in which the alcohol hydroxyl group reacts with sodium metal to replace the hydrogen atom in the hydroxyl group to form hydrogen gas.

5.Substitution reactions can occur, and intermolecular dehydration into ethers (r-o-r) R and R" are hydrocarbon groups.

In many cases, it is easy to confuse hydroxyl and hydroxide because they are written in the same way in the schematic formula.

Differences: 1. The number of electrons is different: the hydroxide group is ten electrons, and the hydroxyl group is nine electrons; 2. The electronic formula of the two is different: the oxygen atom of hydroxide is surrounded by 8 electrons, and the oxygen atom of hydroxyl group is surrounded by 7 electrons.

While hydroxide and hydroxyl are both atomic groups, hydroxyl groups are functional groups, while hydroxides are ions. Moreover, substances containing hydroxide are alkaline in aqueous solution, while aqueous solutions of substances containing hydroxyl groups are mostly acidic. The commonality of hydroxide and hydroxyl groups in organic chemistry is nucleophilicity.

Synthetic protection. Hydroxyl group is one of the most common functional groups in organic chemistry, and both alcoholic and phenolic hydroxyl groups are easily oxidized by a variety of oxidants. Therefore, in the synthesis of polyfunctional compounds, the hydroxyl group or part of the hydroxyl group needs to be protected to prevent it from participating in the reaction and then being converted in the appropriate steps.

Carboxyl is the basic chemical group in organic chemistry, all organic acids can be called carboxylic acids, which are composed of one carbon atom, two oxygen atoms and one hydrogen atom, with the chemical formula -COOH.

The hydroxyl group is a functional group, and the aqueous solution of the hydroxyl group is mostly acidic. The commonality of hydroxyl groups in organic chemistry is nucleophilicity.

A group of monovalent atoms consisting of a carbonyl group and a hydroxyl group is called a carboxyl group. The properties of the carboxyl group are not a simple addition of the carbonyl and hydroxyl groups. For example, the carbonyl group in the carboxyl group becomes very inactive under the influence of the hydroxyl group, and does not undergo addition reaction with nucleophiles such as HCN and NaHSO3, while its hydroxyl group is easier to dissociate than the alcohol hydroxyl group, showing weak acidity.

Hydroxyl group - OH, in organic matter, it is generally mainly alcohol, that is, alcohol hydroxyl group, and its chemical properties are mainly and.

Sodium metal, reacts with acids.

Esterification reaction. The dehydration of the hydroxyl groups into ether reaction, and the oxidation into ketones, aldehydes and finally acid reaction. There is also a phenolic hydroxyl group, such as phenol, due to its subjectivity.

Under the influence of benzene ring, the phenolic hydroxyl group is more active than the alcohol hydroxyl group, and the phenolic hydroxyl group is generally easy to be oxidized.

Carboxyl--COOH, since it is an organic acid, the first thing to pay attention to is that it is acidic. As for the reactions, the ones mentioned in the book are esterification, anhydride, carbon dioxide removal, etc.