Organic Compound Characteristics 9/23/08

organic compound = a compound composed of these four elements, hooked together with covalent bonds: carbon, oxygen, nitrogen, and hydrogen. functional group = an atom or group of atoms that is responsible for the specific properties of an organic compound. If an organic molecule has no functional groups, it’s classified as: saturated hydrocarbon = a hydrocarbon that contains only single bonds (therefore, they are alkanes) unsaturated hydrocarbon = a hydrocarbon that contains one or more double or triple bonds (therefore, they are alkenes or alkynes)

monounsaturated = one double/triple bond on the whole chain polyunsaturated = more than one double/triple bond on the chain Functional groups, once added to the carbon chain, form eight basic types of organic compounds. Each type of compound has its own general formula (as was the case with the simple hydrocarbons). 1. alcohols5. ketones 2. alkyl halides6. carboxylic acids 3. ethers7. esters 4. aldehydes8. amines

1. alcohols = compounds that contain one or more hydroxyl groups. The structure shown above is ethanol. The hydroxyl group could have been placed anywhere on the structure. Alcohols are used in cosmetic products in the form of glycerol (a moisturizing agent found in lotions, lipsticks, antiperspirants, and creams like Noxzema™). Alcohols are metabolized into highly toxic products such as formaldehyde (used to preserve dead bodies) and formic acid (the “sting” in an ant bite). Ingestion of methanol can lead to optic nerve damage, coma, and death. General Formula: R―OH H H ׀ H−C−C−OH ׀ H H Note: the O and the H do have a bond between them, but is not usually shown in organic structures.

2. alkyl halides = compounds that contain one or more halogen atoms, that are substituted for a hydrogen atom in a hydrocarbon. The structure shown above is dichlorodifluoromethane. This chemical is more commonly called Freon-12, and was once used as a refrigerant, before it was discovered to be a major factor in ozone depletion. Teflon is a widely used alkyl halide (C 2 F 4 ) on cookware. General Formula: R―X (X stands for any halogen) Cl ׀ Cl−C−F ׀ F

3. ethers = compounds in which two hydrocarbon chains are bonded to the same atom of oxygen. The structure shown above is ethyl propyl ether. Methyl-tertiary-butyl ether (MTBE) is the most widely used ether, used as a gasoline enhancer. Tetraethyl lead (C 2 H 5 Pb) was once widely used for this purpose, until it was found to be an environmental contaminant, releasing too much lead into the environment. General Formula: R―O―R H H H H H ׀ ׀ ׀ ׀ ׀ H−C−C−O−C−C−C−H ׀ ׀ ׀ ׀ ׀ H H H H H

4. aldehydes = compounds in which the carbonyl group is attached to a carbon atom at the end of a carbon chain. The structure shown above is propanal. Methanal (also known as formaldehyde) is the most widely used aldehyde, used as dead tissue preservative. Simple alcohols and formaldehyde can combine to make certain plastics, such as Bakelite™, one of the first plastics ever made. Some aldehydes are responsible for odors and flavors. Cinnamaldehyde is responsible for the odor of cinnamon (imagine that). General Formula: O  R–C–H H H O ׀ ׀  H−C−C−C−H ׀ H H

5. ketones = compounds in which the carbonyl group is attached to the carbon atoms within the carbon chain. The structure shown above is 3-hexanone. The simplest ketone is 2-propanone (also known as acetone). It is the most widely used ketone, used as a nail-polish remover and degreaser. Some ketones are responsible for odors and flavors. Irone is responsible for the odor of an iris flower (imagine that). General Formula: O  R–C–R H H O H H H ׀ ׀  ׀ ׀ ׀ H−C−C−C−C−C−C−H ׀ ׀ ׀ ׀ ׀ H H H H H

6. carboxylic acids = compounds which contain the carboxyl group, attached to a carbon atom at the end of a carbon chain. The structure shown above is ethanoic acid (also known as acetic acid, the main flavoring agent in vinegar). A number of carboxylic acids occur in citrus fruits, such as oranges, lemons, and limes. Citric acid has a tart flavor, and sorbic acid can be used as an anti- bacterial agent, since it kills microorganisms. Methanoic and ethanoic acids are the starting materials for many chemical processes, including the production of PVA, used in latex paint, adhesives, and textile coatings like Scotchguard™. General Formula: O  R–C–OH H O ׀  H−C−C−OH ׀ H

7. esters = compounds which contain the carboxyl group, with the H from the –OH group removed, and an additional hydrocarbon chain added. The structure shown above is ethyl butanoate. This compound is responsible for the odor of pineapple. Esters are also responsible for fruit ripening. Grocery stores spray esters on unripened fruit in order to get them to ripen in the store. General Formula: O  R–C–O–R H H H O H H ׀ ׀ ׀  ׀ ׀ H−C−C−C−C−O−C−C−H ׀ ׀ ׀ ׀ ׀ H H H H H + ester 

8. amines = compounds which can be considered derivatives of ammonia, NH 3. Amines are found in a variety of neurotoxins, produced by poisonous animals. Batrachotoxin interferes with proper nerve cell functioning, so a continuous firing happens, resulting in cell death. Others are responsible for odors, like putricine and cadaverine, along with skatole (feces) and methylamine (dead fish). Still others are known as alkaloids, and include compounds that have physiological effects, such as caffeine, nicotine, and morphine. General Formula: R–N–R’ | R”