Aromatic compounds contain what kind of ring

Benzene itself is a clear, colorless, highly flammable liquid, which boils at It was used extensively as a solvent for many organic reactions, but it is toxic by ingestion and inhalation, and may cause bone marrow problems or leukemia with prolonged exposure. Toluene 3D Download 3D Toluene or methylbenzene is a commonly used organic solvent; it is less carcinogenic than benzene because the methyl group is easily oxidized, and can be converted to products that can be eliminated from the body with relative ease.

Toluene was first isolated from the gum of the Toluifera balsamum tree of South America, which produces a balsam that has been used in cough syrups and perfumes. Xylene 3D ortho -xylene ortho -dimethylbenzene 1,2-dimethylbenzene Download 3D meta -xylene meta -dimethylbenzene 1,3-dimethylbenzene Download 3D para -xylene para -dimethylbenzene 1,4-dimethylbenzene Download 3D There are three structural isomers of the xylenes , which have two methyl groups on the benzene ring.

The methyl groups may be on adjacent carbons ortho , they may be on carbons separated by one other carbon meta , or they may be on opposite sides of the benzene ring para.

Xylol is a common industrial solvent which contains a mixture of all three xylene isomers. Toluene and the xylenes are found in high-performance BTX gasoline. Aniline 3D Download 3D Aniline is a colorless, oily liquid. It is easily converted into a number of other useful organic compounds, and is also a component of many dyes and pharmaceutical compounds.

Phenol 3D Download 3D Phenol is a mild acid in aqueous solution where it is known as carbolic acid , and was originally used as a disinfectant in hospitals. For more information on phenol and its derivatives, see the page on Phenols. Benzoic acid and its salts sodium benzoate, potassium benzoate, etc. For more information of benzoic acid and its derivatives, see the page on Carboxylic Acids. Styrene is used in the manufacture of polystyrene and Styrofoam see the section on Addition Polymers.

Benzaldehyde 3D Download 3D Benzaldehyde consists of a benzene ring connected to an aldehyde group a carbon-oxygen double bond bearing a hydrogen, —CHO. Benzaldehyde is partially responsible for the odor of almonds and cherries, and is also found in peach and apricot pits. The natural source of benzaldehyde is a molecule called amygdalin. Amygdalin is a disaccharide consisting of two glucose molecules in which a carbon bearing a cyano CN group and a benzene ring is attached to one of the oxygen atoms on a glucose.

The combination of a cyano group with a OH or OR group on a single carbon is called a cyanohydrin; cyanohydrins easily break down to release the cyanide ion, CN -. Amygdalin occurs in almonds, cherries, and peach and apricot pits. When apricot or peach pits are ground up, the enzyme emulsin breaks down amygdalin, releasing benzaldehyde and hydrogen cyanide, HCN, which is a deadly poison.

This preparation was used by the ancient Egyptians and Romans in making various poisons. Under the name laetrile, amygdalin was used as an anti-cancer drug. It was never approved for sale in the United States, but was a popular "alternative medicine" for use in chemotherapy in other countries. However, more research showed that not only is laetrile ineffective against cancer, it is extremely toxic, due to the release of hydrogen cyanide. Hyacinthin is commonly used in perfumes; it is responsible for the floral scent found in hyacinth oddly enough.

Cinnamaldehyde is found in oil of cinnamon, which is found in the bark of the cinnamon tree. Cinnamon is a carminative — it stimulates the release of gases such as hydrogen sulfide, methane, and hydrogen from the stomach and intestines. These gases can have some interesting social consequences depending on which direction they exit from the digestive tract, but I'll leave that to your imagination.

Anethole 3D Download 3D Anethole is found in oil of aniseed, fennel, and tarragon. Benzyl acetate 3D Download 3D Benzyl acetate is one of the compounds found in oil of jasmine, which is a common ingredient in perfumes and toiletries. Phenylethanol 3D Download 3D Phenylethanol is found in oil of citronella, geraniums, and with geraniol is partially responsible for the odor or roses.

Polycyclic aromatic hydrocarbons consist of two or more benzene rings fused together. They are produced when organic compounds are heated to high temperatures, and are present in tobacco smoke, car exhaust, and sometimes in heavily browned foods. Naphthalene is a white crystalline solid, derived from coal tar, with a characteristic odor of mothballs — which is not a coincidence, since naphthalene is frequently used in mothballs.

Naphthalene consists of two benzene rings that are fused together; the resulting molecule is still aromatic, and undergoes the reactions that are typical of benzene itself. Anthracene 3D Download 3D Anthracene is a white crystalline solid which exhibits a blue fluorescence under ultraviolet light. Phenanthrene 3D Download 3D Phenanthrene is a structural isomer of anthracene, in which the three benzene rings are fused to make an angle.

The lone pairs of electrons on the nitrogen atoms, combined with the rigidity of the aromatic ring system, makes ortho -phenanthroline useful in forming metal complexes. Dibenz[ a,h ]anthracene 3D Download 3D Dibenz[ a,h ]anthracene is a carcinogenic compound found in tobacco smoke and automobile exhaust.

Pyrene 3D Download 3D Pyrene is also a suspected carcinogen. Benzo[ a ]pyrene 3D Download 3D Benzo[ a ]pyrene is a carcinogenic compound found in tobacco smoke and automobile exhaust. Molecules whose Lewis structures can be drawn as a ring with alternating single and double bonds are known as annulenes. Annulenes are named by prefixing the number of carbon atoms in the rings in brackets before the word annulene : hence, benzene can be named as [6] annulene.

Thus, molecules with 2, 6, 10, 14, 18, etc. This particular resource used the following sources:. Skip to main content. Organic Chemistry. Search for:. Properties of Aromatic Compounds. Learning Objective Recognize the general properties of aromatic compounds. Draw a resonance structure for it. It has a purine core. Of the nitrogen in the core, how many electrons are donated into the pi system? All of the other nitrogens are sp2 hybrized and contribute 1 pi electron each. In total, the core is aromatic with 10 electrons in the pi-system.

This is an isomer of naphthalene. The following molecule is adenine. There is only one nitrogen of the core that contributes to the pi-system in red. With this one lone pair the core is aromatic with 10 electrons in the pi-system. Steven Farmer Sonoma State University. Objectives After completing this section, you should be able to draw the resonance contributors for polycyclic aromatic compounds, such as naphthalene, anthracene, etc.

Key Terms Make certain that you can define, and use in context, the key term below. Benzene rings may be joined together fused to give larger polycyclic aromatic compounds. A few examples are drawn below, together with the approved numbering scheme for substituted derivatives.

The peripheral carbon atoms numbered in all but the last three examples are all bonded to hydrogen atoms. Unlike benzene, all the C-C bond lengths in these fused ring aromatics are not the same, and there is some localization of the pi-electrons. The six benzene rings in coronene are fused in a planar ring; whereas the six rings in hexahelicene are not joined in a larger ring, but assume a helical turn, due to the crowding together of the terminal ring atoms.