chem 2

• Alcohols contain a hydroxyl group (OH group) bonded to a tetrahedral carbon atom.
• • Alcohols have higher boiling points and melting points than hydrocarbons of comparable size and shape.
• • Alcohols are soluble in organic solvents.
• • Low molecular weight alcohols (those having less than six carbons) are soluble in water.
• Higher molecular weight alcohols (those having six carbons or more) are not soluble in water
• Ethanol is the alcohol in red wine, obtained by the fermentation of grapes.
• • Starch and cellulose are two polymers that contain many OH groups and belong to the family of molecules called carbohydrates.
• In the IUPAC system, alcohols are identified by the suffix - ol
• Compounds with two hydroxyl groups are called diols (using the IUPAC system) or glycols.
• Methanol (CH3OH) is a useful solvent and starting material for the synthesis of plastics.
• 2-Propanol [(CH3)2CHOH, isopropyl alcohol] is the major com- ponent of rubbing alcohol. When rubbed on the skin it evaporates readily, producing a pleasant cooling sensation.
• Ethylene glycol (HOCH2CH2OH) is the major component of antifreeze. It is sweet tasting but extremely toxic
• Glycerol [(HOCH2)2CHOH] is a triol used in lotions, liquid soap, and shaving cream. Since it is sweet tasting and nontoxic, it is also an additive in candy and some prepared foods.
• When ethanol is consumed, it is quickly absorbed in the

  stomach and small intestines and then rapidly transported in

  the bloodstream to other organs.
• Ethanol is metabolized in the liver, by a two-step oxidation

  reaction sequence.
• The reaction is carried out by enzymes: alcohol

  dehydrogenase and aldehyde dehydrogenase and a small

  molecule called a coenzyme.
• ANTABUSE is a drug given to alcoholics to prevent them from consuming alcoholic beverages.
• Chronic excessive alcohol consumption damages the heart and can lead to CIRRHOSIS OF THE LIVER, an incurable and fatal disorder in which the liver is scarred and loses its ability to function.
• FETAL ALCOHOL SYNDROME can result in infants of women who

  chronically consume alcohol during pregnancy.
• Ethers are organic compounds that have two alkyl groups bonded to an oxygen atom. These two alkyl groups can be the same, or they can be different.
• A ring that contains a heteroatom is called a HETEROCYCLE
• When the ether is part of a three-membered ring, the ether is called an EPOXIDE.
• • Ethers have higher melting points and boiling points than hydrocarbons of comparable size and shape
• • Ethers have lower melting points and boiling points than alcohols of comparable size and shape.
• All ethers are soluble in organic solvents. Low molecular weight ethers are water soluble, because of the oxygen that can hydrogen bond to one of the hydrogens of water.
• • When one of the alkyl groups of ether have more than a total of 5 carbons, ether becomes insoluble in water.
• Simple ethers are usually assigned common names.

  Complex ethers are named using the IUPAC system.
• For reasons of being highly flammable and nauseating for many patients, diethyl ether has largely been replaced by HALOTHANE which is non-flammable and causes little patient discomfort.
• Naturally occurring compounds that contain epoxides include periplanone B, the sex pheromone of the female American cockroach, and epothilone B, a novel anticancer drug isolated in 1987 from soil bacteria in southern Africa
• Name the simpler alkyl group as an alkoxy substituent by changing the –yl ending of the alkyl group to – oxy.
• Alkyl halides contain a polar C-X bond, wherein X is any halogen.
• • The boiling point and melting point of an alkyl halide increase with the size of the alkyl group because of increased surface area.
• • The boiling point and melting point of an alkyl halide increase with the size of the halogen.
• Common names for alkyl halides are used only for simple alkyl halides. To assign a common name, name the carbon atoms as an alkyl group. Then name the halogen by changing the –ine ending of the halogen name to the suffix ide; for example, bromine → bromide.
• • Chloromethane (CH3CI) is produced by giant kelp and algae and is also found in emissions from volcanoes such as Hawaii's Kilauea. Almost all of the atmospheric chloromethane results from these natural sources.
• • Dichloromethane (or methylene chloride, CH2Cl2) is an important solvent, once used to decaffeinate coffee. Coffee is now decaffeinated using liquid CO₂ due to concerns over the possible ill effects of trace amounts of residual CH2Cl2 in the coffee. Subsequent studies on rats have shown, however, that no cancers occurred when animals ingested the equivalent of over 100,000 cups of decaffeinated coffee per day.
• Chlorofluorocarbons are simple halogen-containing compounds that have caused lasting harm to the environment.
• Thiols are organic compounds that contain a sulfhydryl group (SH

  group) bonded to a tetrahedral carbon.
• Since sulfur is directly below oxygen in the periodic table, thiols can

  be considered sulfur analogues of alcohols.
• Because the sulfur atom is surrounded by two atoms and two lone

  pairs, thiols have a bent shape around sulfur.