FUNCTIONAL GROUPS

• ORGANIC CHEMISTRY It is the study of Carbon containing compounds It is used as a source of foods, clothing, fuels, and medicine and are mostly found in nature
• Organic compounds are mainly composed of Carbon and Hydrogen and may bond with other elements such as Oxygen and Nitrogen. Organic compounds are essentially covalent bonds.
• Identify the properties

  A) Number of Atoms Formula of Alkane Name No. of Isomers

  
• General characteristics of Organic and Inorganic Compounds:

  ORGANIC:

  All are carbon compounds

  Covalent bond

  Low melting point

  Low boiling point

  Most are nonelectrolytes

  INORGANIC:

  Contains metals in salts and oxides

  Ionic bond

  High melting point

  High boiling point

  Many are electrolytes
• Functional Groups

  • Classes of organic compounds can be distinguished according to their functional groups.
  • A functional group is a group of atoms that is largely responsible for the chemical behavior of the parent molecule.
• The isomers contain different functional groups with different orientation.

  Example: propanone (a ketone) and propanal (an aldehyde)
• Structural Isomer

  • another example of an isomer is propanoic acid (a carboxylic acid) and methyl ethanoate (an ester)
• Identify which structural isomers are these:

  1. Propanoic Acid
  2. Hydroxyl
  3. Methylethanoate

  
• Hydroxyl Functional Group

  • Also known as the alcohol group.
  • It consists of a hydrogen atom covalently bonded to an oxygen atom.
  • The hydroxyl group is denoted by –OH in the chemical structures
  • It is present in the alcohol and carboxylic acid molecules.

  
• Methanol or methyl alcohol, also known as wood alcohol, is toxic and can cause blindness or death when ingested.
• Ethanol or Ethyl alcohol, the alcohol associated with alcoholic beverages, is made by adding yeast to solutions rich in sugars or starches.
• The yeast cells obtain energy from enzyme catalyzed reactions that convert sugar or starch to ethanol and CO2.
• 1-propanol or propanol is a colorless liquid that is formed naturally in small amounts during fermentation and used as a solvent in the pharmaceutical industry mainly for resins and cellulose esters.
• Isopropyl alcohol is commonly used as an antiseptic solution and disinfectant.
• Memorize these!

  
• Aldehyde Functional Group - In the aldehyde, at least one hydrogen atom is bonded to the carbon in the carbonyl group.

  
• Aldehyde Functional Group

  1. Formaldehyde -Is the simplest aldehyde. It is usually prepared and stored in an aqueous solution which is usually accompanied with an unpleasant smell. In the laboratory, it is used as a preservative for various types of specimens.

  
• 2. Ethanaldehyde or Acetaldehyde - It is produced by partial oxidation of ethanol by the liver enzyme alcohol dehydrogenase that may be a contributing factor to the hangovers from alcohol consumption.

  
• Ketones Functional Group - In a ketone, the carbon atom in the carbonyl group is bonded to two hydrocarbon groups.

  
• KETONES FUNCTIONAL GROUPS

  1. Propanone - Is also known as Acetone. It is the simplest ketone. A pleasant-smelling liquid that is used mainly as a solvent for organic compounds and used as a nail polish remover. When a ketone is released in the body it signals that there is the breakdown of fats which is a common complication experienced by patients with Diabetes. A diabetic patient may experience frequent urination (polyuria), frequent thirst (polydypsia) and always feels hungry because of the breakdown of fats (polyphagia). The ketones may also be released in the kidneys via urine (Ketonuria)

  
• Carboxylic Acids

  • Many organic compounds are characterized by the presence of –COOH group known as “Carboxyl groups.”
  • This was the name that was derived by the contraction of the term's carbonyl (C=O) and hydroxyl (OH), hence such acids are called “Carboxylic acids”

  
• Carboxylic Acids

  1. (IUPAC) Methanoic acid (Common name) Formic acid - Preservative agent, antibacterial agent, when we were bitten by ants, it stings because it also contains formic acid.
  2. . (IUPAC) Ethanoic acid (Common name) Acetic acid - A solution of acetic acid and water is vinegar.
  3. . (IUPAC) Butanoic acid (Common name) Butyric acid - Butyric acid is present in vomitus which is responsible for its distinctive smell. It is also produced by some of the bacteria such as Clostridium butyricum and Butyvibrio fibrisolvens.
• 4. (IUPAC) Hexanoic acid (Common name) Caproic acid - It is used as a food flavoring agent in butter, milk, strawberry, beer, nuts and other flavors

  5. (IUPAC) Octadecanoic acid (Common name) Stearic acid - Mainly used in the production of detergents and soap and other cosmetics such as the shampoo and shaving cream.
• Esters Functional Group

  Esters are produced by the reaction of acids with alcohols. Esterification is the reaction between carboxylic acid and an alcohol in which an acid catalyst (usually the Sulfuric acid) is present, and heat is applied. In the reaction, water formed by an _OH from the carboxylic acid and H from the alcohol is removed from the reacting molecules. Presence of one or more esters in many flowers and ripe fruits can give a distinctive and attractive odor and flavor.

  
• Sources of Esters and Their Biological Importance

  Esters widely occur in nature, most especially in fruits and flowers. In facts many esters are used as artificial flavorings like the following:

  ❖ Amyl Acetate for banana,

  ❖ Ethyl Butyrate for pineapple,

  ❖ Octyl acetate for orange and isobutyl propionate for rum.

  ❖ Isobutyl formate for Raspberries

  ❖ Propyl ethanoate for pears

  ❖ Methyl thiobutyrate for strawberries
• Amides Functional Group

  Are derivatives of the carboxylic acids in which the hydroxyl group is replaced by an amino group. There may also be one or two alkyl groups attached to the nitrogen atom in the amide. Amides are mostly used as medications in the health industry. They may be used to kill bacterial (antibiotic) or relieve pain (analgesic), decrease fever (anti pyretic) and may relieve anxiety.

  
• Sulfadrugs are amides of sulfonic acids (RSO3H) and are effective antibiotics in treating bladder infection.
• Examples of these antibiotics include Benzenesulfonamide and Sulfaniamide.
• Urea is the simplest natural amide and is the product of protein catabolism.
• Saccharin is an artificial sweetener.
• Acetaminophen/ Tylenol is used to relieve pain (analgesic) and decrease fever (antipyretic).
• Diazepam / Valium is used to relieve anxiety.
• Lidocaine/ Xylocaine is commonly used as an anesthesia because it is non-irritating and hypoallergenic.
• Bupivacaine/ Marcaine is used as a spinal anesthesia.
• Amines Functional Group

  • The element of nitrogen plays an important role in the physiological activities of compounds such as antibiotics, tranquilizers, alkaloids and amphetamines.
  • Some of the amines are used as anti-histamine (blocks the effect of histamine), central nervous stimulant (CNS stimulant), neurotransmitters (sends impulses to the brain).
• Histamine is released in response to allergic reaction or injury to cells, causing the blood vessels to dilate and increasing the permeability of the cells, leading to redness and swelling in the area.
• Diphenhydramine, also known as Benadryl, helps block the effects of histamine (anti histamine).
• Epinephrine, also known as Adrenaline, increases the energy of the person because of the sudden increase of glucose in the body which allows the person to move faster in emergency case situation, an example of this phenomenon is carrying a refrigerator during a fire.
• Norepinephrine, also known as Noradrenaline, affects the sleep wake cycle and increases blood sugar levels to provide energy to the body.
• Decreased levels of Norepinephrine may lead to depression.