How are the carbon atoms of anthracene numbered, and how are the carbon atoms in organic numbered

The original carbon number of anthracene is shown below

Anthracene (also called scintillation crystal), a fused aromatic hydrocarbon containing three rings.

Molecular formula C14H10, solid polycyclic aromatic hydrocarbon.

Composed of triphenyl medium, which is present in the center of the three rings of coal tar, anthracene in a straight line, is an isomer of phenanthrene.

The 1,4,5,8 positions in the anthracene molecule are the same, called -position;

2,3,6,7 are also the same, called -bit;

9,10 two digits are the same, called the -position, or median.

Thus, there are three isomers of the monosubstituent of anthracene. The number of carbon atoms in the anthracene molecule is shown below

Anthracene is a triphenyl medium composed of solid polycyclic aromatic hydrocarbons. It is found in coal tar. The center of the three rings of anthracene is in a straight line and is an isomer of phenanthrene.

Anthracene is a colorless flaky crystal; blue-violet fluorescence; Melting point 215, boiling point 340, relative density; easy to sublimate; Insoluble in water, insoluble in ethanol and ether, soluble in hot benzene.

1. In the naphthalene molecule, the C atom on the covalent bond does not have hydrogen, so it is not left alone when numbering.

2. There are 4 c atoms closest to the covalent bond, numbered as carbon atom No. 1.

3. Then number along one side of the ring, and then knit another after the ring is braided, in which the carbon atom numbered 8 will definitely be very close to the No. 1 carbon atom.

4. The four carbon atoms that are close to the common bond when there are no substituents are called carbon atoms, and the other four are called carbon atoms, and the numbers start from carbon atoms and end with carbon atoms.

5. When there are three or more groups on the ring, if the configuration is expressed by cis, anti, a reference group should be selected, usually the group at the 1 position is selected as the reference group, represented by r-1, and placed at the front of the name.

In the anthracene molecule, the two rings share a covalent bond. The c atom on this bond does not have hydrogen, so it is not numbered. There are four c atoms closest to this bond, and they can all be the first carbon atom, and then one ring is numbered along the side of the ring, and then another ring is numbered, and carbon atom 8 must be very close to carbon atom 1.

In the absence of substituents, the carbon atom of hydrogen in the anthracene molecule can be divided into two categories. One is the four carbon atoms that are close to the common bond and are called the -carbon atom and the other four are called the -carbon atom. The number must start with - carbon atom and end with - carbon atom.

Other PAHs also have similar amounts, starting with a complete benzene ring.

1. For alkanes, after determining the backbone, the number should first make the substituent's number smallest, and if the substituent's number is the same, the small substituent's number should be minimized.

2. For compounds with functional groups, the longest carbon chain containing functional groups should be selected as the main chain, and the number of the main chain should be the smallest number of functional groups. For example, in the case of alkenes, the double-bonded carbon atom should be minimized; In the case of alcohol, the hydroxyl group should be minimized.

It generally starts with the functional group. On the premise above, keep the numbers as low as possible.

1. Single ring. 1. According to the carbon atom in the ring.

The total number is named "Cyclic hydrocarbon".

2. The position and number of the substituents on the ring are written in front of the name of the parent cyclic hydrocarbon, and the "numbering" principle is related to the chain hydrocarbon.

Same. 3. If the subplacent's carbon chain is long, the ring acts as the substituent. I would like to argue.

4. Marking cis-negative or R s cannot be marked at the same time.

Second, the nomenclature of cyclic olefins.

1. Name the ring according to its size

Cycloethylene. 2. The sum of the numbers of the double-bonded carbon atoms is not small.

3. Number in the direction of making the other substituents on the ring as small as possible.

The above people are quite right, only the carbon atom is numbered, if there is a Youchang heteroatom, the heteroatom is numbered first, and the rock disturbance has a fixed number for purine, pyrimidine, thiophene, imidazole, furan, etc., and you need to write down the rough denier yourself.

If there is no side chain, there is no number, if there is a side chain, the sum of all side chain positions should be minimized, and if there is a functional group, the functional group position should be the smallest.

First, the single ring in Tong's.

1. According to the total number of carbon atoms in the ring, it is named "a certain hydrocarbon in the ring".

2. The position and number of the substitutes on the ring are written in front of the name of the parent cyclohydrocarbon, and the principle of "numbering" is the same as that of the chain hydrocarbon.

3. If the subplacent's carbon chain is long, the ring acts as the substituent.

4. Marking cis-negative or R s cannot be marked at the same time.

Second, the nomenclature of cyclic olefins.

1. The size of the root selling bulk ring is named "ring a certain ene".

2, The sum of the numbers of the double-bonded carbon atoms is the smallest.

3. Number in the direction of making the number of other substituents on the ring as small as possible.