Base Organic Chemicals

Classified by carbon skeleton

1. Chain compound

The carbon atoms in the molecules of this kind of compound are linked together in chains, and are also called aliphatic compounds because they were originally found in fats. A structural feature is that carbon and carbon are linked by a closed chain.

2. cyclic compounds

A cyclic compound refers to a compound in which atoms in a molecule are arranged in a ring form. Cyclic compounds are divided into alicyclic compounds and aromatic compounds.

(1) alicyclic compound: a compound having a ring that does not contain an aromatic ring (eg, a benzene ring, a fused ring or a benzene ring, or a specific heterocycle having a fused ring property). cyclopropane, cyclohexene, cyclohexanol, and the like.

(2) Aromatic compound: A compound having a ring containing an aromatic ring (such as a benzene ring, a condensed ring, or a benzene ring or some heterocyclic ring having properties of a condensed ring). Benzene, benzene homologues and derivatives, fused ring aromatic hydrocarbons and derivatives, pyrrole, pyridine, etc.

According to structure and nature

Open Chain Hydrocarbons: The carbon atoms in a molecule combine to form a chain without a ring structure, which is called an open chain hydrocarbon. According to the content of carbon and hydrogen in the molecule, chain hydrocarbons can be divided into saturated chain hydrocarbons (alkanes) and unsaturated chain hydrocarbons (alkenes, alkynes).

Aliphatic Hydrocarbons: Also called "chain hydrocarbons". Since fats are derivatives of chain hydrocarbons, chain hydrocarbons are also called aliphatic hydrocarbons.

Saturated Hydrocarbons: Saturated hydrocarbons can be divided into chain saturated hydrocarbons, i.e. alkanes (also called paraffinic hydrocarbons), and another type of cyclic saturated hydrocarbons containing carbon-carbon single bonds, i.e. cycloalkanes (see Closed Chain Hydrocarbons).

Alkanes: Saturated chain hydrocarbons, also called paraffinic hydrocarbons. The general formula is CnH2n+2 (n≥1) and the hydrogen content of the alkane has reached saturation. The simplest alkanes are methane, the main component of natural gas and biogas, and the main sources of alkanes are petroleum, natural gas and biogas. Methane can undergo a substitution reaction with chlorine under bright conditions and the product is CH3Cl→CH2Cl2→CHCl3→CCl4.

Unsaturated Hydrocarbon: A hydrocarbon containing unsaturated bonds (“C=C” or “C≡C”) in its molecule. These hydrocarbons can also be divided into unsaturated chain hydrocarbons and unsaturated cyclic hydrocarbons. Unsaturated chain hydrocarbons contain fewer hydrogen atoms than their corresponding alkanes, are chemically active, and are susceptible to addition and polymerization reactions. Unsaturated chain hydrocarbons can be divided into alkenes and alkynes. Unsaturated cyclic hydrocarbons can be divided into cycloalkenes (eg cyclopentadiene) and cycloalkynes (eg benzine).

Olefin: A hydrocarbon containing "C=C" in the molecule. According to the number of "C=C" in the molecule, it can be divided into monoolefins and diolefins. Monoolefin molecules contain "C=C" and have the general formula CnH2n, where n≥2. The most important monoolefins are ethylene H2C=CH2, the second being propylene CH₃CH=CH₂ and 1-butene CH₃CH₂CH=CH₂. Monoolefins are called olefins, and the main sources of olefins are petroleum and its cracked products.

Diolefin: a chain or cyclic hydrocarbon containing two "C=C". such as 1,3-butadiene. Among dienes such as 2-methyl-1,3-butadiene and cyclopentadiene, the most important is a conjugated double bond system. For example, 1,3-butadiene and 2-methyl-1,3-butadiene are monomers of synthetic rubber.

Alkyne: An unsaturated chain hydrocarbon containing "C≡C" in its molecule. According to the number of carbon-carbon triple bonds in the molecule, it can be divided into mono-alkynes and poly-alkynes, the general formula of mono-alkynes is CnH2n-2, where n≥2. Alkynes and dienes are isomers. The simplest and most important alkyne is acetylene HC≡CH, which can be produced by the reaction of calcium carbide with water.

Closed-bonded hydrocarbons: Also called "cyclic hydrocarbons". It is a hydrocarbon with a ring structure. One is alicyclic hydrocarbons (or alicyclic hydrocarbons) with aliphatic properties, which are further divided into saturated naphthenes with n≥3. Cycloalkanes and alkenes are isomers. Cycloalkanes are found in some petroleum oils, and cycloalkenes are often found in plant essential oils. Another type of cyclic hydrocarbon is aromatic hydrocarbons, and most aromatic hydrocarbons have a benzene ring structure and properties of aromatic compounds.

Cycloalkanes: In cyclic hydrocarbon molecules, the carbon atoms are joined to each other by single bonds called cycloalkanes, which are saturated alicyclic hydrocarbons. Cycloalkanes with tricyclic and tetracyclic rings have poor stability and can be easily opened under certain conditions. Cycloalkanes with 5 or more rings are relatively stable and have properties similar to alkanes. Common cycloalkanes are cyclopropane, cyclobutane, cyclopentane, and cyclohexane.

Aromatic Hydrocarbons: Refers to hydrocarbons that usually contain a benzene ring structure in their molecule. According to the number of benzene rings contained in the molecule and the connection method between the benzene rings, it can be divided into monocyclic aromatic hydrocarbons, polycyclic aromatic hydrocarbons, condensed ring aromatic hydrocarbons, etc. The general formula of monocyclic aromatic hydrocarbons is CnH2n-6, where n≥6, and among monocyclic aromatic hydrocarbons, benzene and methylbenzene are important.

Condensed Ring Aromatic Hydrocarbons: There are two or more benzene rings in the molecule and two carbons are shared between the benzene rings. [11]

Heterocyclic Compounds: Compounds that contain carbon atoms and oxygen, nitrogen, sulfur and other atoms in their molecules to form a ring structure are called heterocyclic compounds. Among them, 5-membered and 6-membered heterocycles are more stable. Those with aromatic properties are called aromatic heterocycles.

Halogenated Hydrocarbons: Compounds formed by replacing one or more hydrogen atoms in a hydrocarbon molecule with a halogen atom are called halogenated hydrocarbons. According to the different halogen atoms substituted, it can be divided into fluorohydrocarbons, chlorinated hydrocarbons, brominated hydrocarbons and iodohydrocarbons. According to the number of halogen atoms in the molecule, it can be divided into monohalogenated hydrocarbons and polyhalogenated hydrocarbons. According to the different types of hydrocarbon groups, it can be divided into saturated halogenated hydrocarbons, that is, halogenated alkanes, unsaturated halogenated hydrocarbons, that is, halogenated alkenes and halogenated alkynes, halogenated aromatic hydrocarbons, etc. Chlorine CH3-CHBr-CH2Br and the like. Halogenated hydrocarbons can undergo hydrolysis and removal reactions, and some halogenated hydrocarbons can react with magnesium (see Grignard's reagent).

Alcohol: A product in which one or several hydrogen atoms in a hydrocarbon molecule have been replaced by a hydroxyl group is called an alcohol (when a hydrogen atom in a benzene ring is replaced by a hydroxyl group, the product is a phenol). According to the number of hydroxyl groups in the alcohol molecule, it can be divided into monohydric alcohols, dihydric alcohols, trihydric alcohols, etc. According to the difference in the hydrocarbon group of the alcohol molecule, it can be divided into saturated alcohol, unsaturated alcohol alcohol and aromatic alcohol. Due to the position of the carbon atom attached to the hydroxyl group, it can be divided into tertiary alcohols such as (CH3)3COH. Alcohols are generally neutral, lower alcohols are readily soluble in water, and polyols are sweet with o-hydroxyl groups. Chemical reactions of alcohols mainly include oxidation reactions, esterification reactions, dehydration reactions, reactions with halogen acids, and reactions with active metals. Adjacent diols can react with divalent copper ions.

Aromatic alcohol: A substance in which the hydrogen atom on the side bond of the benzene ring in an aromatic hydrocarbon molecule is replaced by a hydroxyl group. Same as benzyl alcohol (also called benzyl alcohol).

Phenol: A compound in which the hydrogen atom in the benzene ring of an aromatic hydrocarbon molecule is replaced by a hydroxyl group is called a phenol. Depending on the number of hydroxyl groups included in the phenol molecule, it can be divided into monohydric phenols, dihydric phenols, polyhydric phenols, etc., such as a color change reaction of a solution. Phenol has a weak acidity and can react with alkalis to form phenates. The benzene ring of the phenol molecule is susceptible to halogenation, nitration, sulfonation and other substitution reactions under the influence of hydroxyl groups, but it is difficult to remove. Ether: A compound formed by linking two hydrocarbon groups through an oxygen atom is called an ether. It can be represented by the general formula R-O-R'. If R and R' are the same, it is called a simple ether, such as methyl ether CH3-O-CH3 or ether C2H5-O-C2H5, and if R and R' are different, it is called a mixed ether. as methyl ether CH3-O-C2H5.

Aldehyde: A compound in which at least one end of a carbonyl group is directly linked to a hydrogen. According to the number of aldehyde groups in the aldehyde molecule, it can be divided into monoaldehyde, dialdehyde, etc., and according to the different hydrocarbon groups in the molecule, it can be divided into the corresponding primary alcohol oxidation product (however, formaldehyde is made by CH₃OH oxidation. The carbonyl group of aldehyde The hydrogen linked to can undergo addition reactions and is easily oxidized to the corresponding carboxylic acid by weak oxidizing agents (i.e. silver ammonia solution) such as Fehling's reagent and Doren's reagent Important aldehydes are formaldehyde, acetaldehyde, etc.

Aromatic Aldehydes: Aldehydes formed by the direct connection of the aldehyde group of a molecule to a benzene ring are called aromatic aldehydes. such as benzaldehyde.

Carboxylic acid: A compound formed by combining a hydrocarbon group or a hydrogen atom with a carboxyl group is called a carboxyl group. Depending on the number of carboxyl groups, it can be divided into monobasic acid, dibasic acid, and polybasic acid. acid, etc. Propionic acid, such as saturated acetic acid, such as CH3CH2COOH, and monobasic acid, such as unsaturated acid, such as acrylic acid, CH2=CH-COOH. Carboxylic acids can also be divided into fatty acids, cycloaliphatic acids and aromatic acids. Among the fatty acids, saturated is stearic acid C17H35COOH and the like.

Carboxylic Acid Derivatives: Compounds formed by replacing the hydroxyl group in the carboxyl group of a carboxylic acid molecule with another atom or group of atoms are called carboxylic acid derivatives. such as acid halides, amides, acid anhydrides, etc.

Acid halide: A compound formed by replacing the hydroxyl group of the carboxyl group of a carboxylic acid molecule with a halogen atom.

B. Amide: A compound in which the hydroxyl group of the carboxyl group of a carboxylic acid molecule is substituted with an amino-NH2 or hydrocarbon amino group (-NHR or -NR2), which can also be regarded as hydrogen. A compound substituted with an acyl group.

c. Acid Anhydrides: Compounds formed by the loss of water between two molecules of a monocarboxylic acid or within a molecule of a dicarboxylic acid are called acid anhydrides. For example, two acetic acid molecules lose one water molecule to form acetic anhydride (CH3COOOCCH3).

Ester: A compound formed by substituting an alkoxy group for the hydroxyl group of the carboxyl group of a carboxylic acid molecule -O-R'

Grease: Generic term for higher fatty acid glycerides. At room temperature, liquid is called oil and solid is called fat. If R, R' and R" are the same, it is called a monoglyceride, and if R, R', R" are different, it is called a mixed glyceride. Most natural oils and fats are mixed glycerides. Nitro Compounds: Hydrocarbons

Chemical nature

1. Mostly flammable

2. Most poor stability (organic compounds often decompose and deteriorate under the influence of temperature, bacteria, air or light)

3. The reaction rate is relatively slow

4. complex reaction products

In general, with the exception of a few organic compounds, they can generally be combusted. It has relatively low thermal stability compared to inorganic materials, and the electrolyte is easily decomposed by heat. The melting point of organic matter is relatively low and usually does not exceed 400°C. The polarity of organic matter is so weak that most of it is insoluble in water.

Most of the reactions between organic substances are intermolecular reactions and require a certain amount of activation energy, so the reaction is slow and the addition of a catalyst or the like is often required. Also, reactions in organic matter are more complex. Under the same conditions, compounds can often perform several different reactions simultaneously to produce different products.

Physical properties

State

Solid: saturated high fatty acid, fat, TNT, naphthalene, phenol, glucose, fructose, maltose, starch, cellulose, acetic acid (below 16.6℃)

Gases: alkanes, alkenes, alkynes, formaldehyde, monochloromethane with less than 4 carbon atoms

Liquid Oil: nitrobenzene, bromoethane, ethyl acetate, oleic acid

Viscosity: ethylene glycol, glycerol

Odor

Odorless: methane, acetylene (often odorous due to the mixture of PH3, H2S and AsH3)

Slight smell: special smell of ethylene; benzene and its homologues, naphthalene, petroleum, phenol

Irritant: formaldehyde, formic acid, acetic acid, acetaldehyde

Sweetness: ethylene glycol, glycerol, sucrose, glucose

Fragrance: ethanol, lower ester

Bitter almond flavor: Nitrobenzene

Color

White: glucose, polysaccharide

Light yellow: TNT

Black or dark brown: petroleum

Water soluble

Poor water solubility: gasoline, carbon tetrachloride, ether, and benzene.

Insoluble: higher fatty acids, esters, nitrobenzene, bromobenzene, alkanes, alkenes, alkynes, benzene and homologs, naphthalene, anthracene, halogenated hydrocarbons, TNT.

Soluble: Phenol (Slightly soluble at 0℃)

Slightly soluble: acetylene, benzoic acid

Easily soluble: formaldehyde, acetic acid, ethylene glycol, benzenesulfonic acid

Miscible with water: lower alcohol, phenol (above 70℃), acetaldehyde, formic acid