- Alcohols R—OH Functional Group = hydroxyl group = OH Alcohol names all end in –ol. Numbers tell which C atom the OH is attached to. Ex: 1-propanol parent: propane molecular: C3H7OH empirical: C3H8O structural: CH3CH2CH2OH H C OH Because it has 1 OH, it is a monohydroxy alcohol The OH group makes alcohols polar. Alcohols dissolve in water because H2O is polar: OH + - H O +
Compare: Alcohols Bases OH group: covalently attached an ion in solution electrolyte: no yes water soluble… yes yes because…. OH is polar OH- is ion Ex. 1,2-ethanediol is a dihydroxy alcohol (two OH groups) Ex. 1,2,3-propanetriol is a trihydroxy alcohol (three OH groups) H C (aka ethylene glycol) O H O H H C (aka glycerol) O H O H O H
ethylene glycol O H C Ethylene glycol is widely used as an automotive antifreeze and a precursor to polymers. In its pure form, it is an odorless, colorless, syrupy, sweet-tasting liquid. Ethylene glycol is toxic, and ingestion can result in death.
--> clear, sweet tasting, oily liquid Glycerin (glycerol): --> clear, sweet tasting, oily liquid --> used to keep dried fruits and pastry fillings moist, in toothpaste, hand creams, eye and ear drops, suppositories (for laxatives, eg), and as an antifreeze Also: glycerin + nitric acid --> glycerol trinitrate aka nitroglycerin (dynamite) H2SO4 for drying
Ex. ethanol (ethyl alcohol) = drug, solvent, fuel parent: ethane molecular: C2H5OH empirical: C2H6O condensed: CH3CH2OH H C OH Ex. Alcohols can also be classified as: 1/ primary: OH attached to an end C as in ethanol 2/ secondary: OH is attached to a C that is directly attached to two other C atoms. At right: 2-butanol 3/ tertiary: OH is attached to a C that is directly attached to three other C atoms At right: 2-methyl, 2-propanol H C O H C O
Ex. For each example below, give the name. Circle if a mono-, di-, or trihydroxy and if a primary, secondary or tertiary alcohol. 1/ 3/ name: _________________ name: ________________ type: mono- di- tri- type: mono- di- tri- class: prim. sec. tert. class: prim. sec. tert. 2/ 4/ OH H C K OH methanol KOH H C O H C H C H C H C H C H C H H O H O H O H 2,3,4-hexanetriol 3-methyl, 2-pentanol
Ethers - two C chains joined by an oxygen O “bridge” Formula: R—O—R‘ Name: (name R without -ane) + oxy + name of R‘ Ex. methoxymethane aka: dimethyl ether molecular: C2H6O condensed: CH3OCH3 Ex. methoxyethane aka: methyl ethyl ether molecular: C3H8O condensed: CH3OCH2CH3 H C O H C O
Ethers are common in organic chemistry and pervasive in biochemistry, as they are common linkages in carbohydrates and lignin.
D. Aldehydes: When a carbonyl group (—C=O) replaces the CH2 at the end of a hydrocarbon Formula R—C—H Name: replace –e with –al Ex. methane: methanal: aka: formaldehyde molecular: CH2O structural: HCOH Ex. ethane: ethanal: aka: acetaldehyde molecular: C2H4O structural: CH3COH or: CH3 O H C O C H O C H C H C H O C
Carbonyl group: C=O Formaldehyde was the first polyatomic organic molecule detected in the interstellar medium[6] and since its initial detection has been observed in many regions of the galaxy.
Carbonyl group: C=O Acetaldehyde occurs naturally in coffee, bread, and ripe fruit, and is produced by plants as part of their normal metabolism. It is also produced by oxidation of ethanol and is popularly believed to be a cause of hangovers.[2]
E. Ketones: When a carbonyl group (—C=O) replaces a C in the interior of a hydrocarbon: Formula: R—C—R' Name: replace –e with –one Ex. propane: propanone: aka: acetone molecular: C3H6O condensed: CH3COCH3 or: CH3CCH3 Ex. Isomers: 2-pentanone and 3-pentanone: condensed: CH3CHOCH2CH2CH3 CH3CH2CHOCH2CH3 O H C H C C O O H C C O H C C O
The word ketone comes from the word: acetone Ketones are produced on massive scales in industry as solvents, polymer precursors, and pharmaceuticals.
Organic Acids are formed by adding the carboxyl group –COOH to a hydrocarbon chain. They are weak acids and weak electrolytes, and are known as carboxylic acids Functional group = --COOH = —C—OH Name: replace –e with –oic acid Ex. ethanoic acid (aka acetic acid in vinegar): molecular: HC2H3O2 condensed: CH3COOH or: CH3 O ethane: ethanoic acid: H C C —OH O H C O C—OH
Ex. A fatty acid is a carboxylic acid –COOH with a long unbranched hydrocarbon chain “tail.” the “fatty” tail the acid Saturated fatty acids: -single C-C bonds -pack closely -solids at room temp -animal “fats” Unsaturated fatty acids: -double C=C bonds bend up the tail -liquids at room temp -vegetable “oils”
Fats and oils are triglycerides Fats and oils are triglycerides. They are formed when the alcohol glycerol combines with 3 fatty acids by condensing out water.
benzoic acid --COOH Used in toothpastes, mouthwashes, cosmetics and deodorants for its antimicrobial properties
ascorbic acid – Vitamin C --COOH
Esters have the functional group: General formula: They are the result of an esterification reaction: organic + alcohol water + ester acid Ex. Sulfuric acid (H2SO4) is used as a catalyst and as a dehydrating agent to remove the water, which is why this is sometimes called condensation reaction. H2SO4
alcohol + acid…es terrifying!
Notice: In the general formula: Naming: The alkyl name of the alcohol is added to the acid group modified to end in –oate or -ate Esters have strong, fragrant aromas and are the cause of the odors and flavors of pineapple, banana, wintergreen and oranges. Ex. The smell of pineapples is due to ethyl butyrate ethanol + butanoic acid water + ethyl butyrate (alcohol) (ester) this part is from the alcohol this part comes from the acid
ethanol + butanoic acid water + ethyl butyrate (alcohol) (ester) From the acid: From the alcohol: acid: alcohol:
octanol + acetic acid water + octyl acetate (alcohol) (ester) From the acid: From the alcohol: acid: alcohol: