480 likes | 648 Views
Chemistry 2100. Lecture 4. ALCOHOLS ETHERS THIOLS. alcohol. ether. thiol / mercaptan (sulfhydryl). IUPAC Nomenclature. Common Nomenclature. • dialkyl "ether". • "e" "ol" • locator numbers. • alkyl "alcohol". Alcohols.
E N D
Chemistry 2100 Lecture 4
ALCOHOLS ETHERS THIOLS
alcohol ether thiol / mercaptan (sulfhydryl)
IUPAC Nomenclature Common Nomenclature • dialkyl "ether" • "e" "ol" • locator numbers • alkyl "alcohol"
Alcohols Alcohol: A compound that contains an -OH(hydroxyl) group bonded to a tetrahedral carbon. • Methanol, CH3OH, is the simplest alcohol. Nomenclature 1. Select the longest carbon chain that contains the -OH group as the parent alkane and number it from the end that gives the -OH the lower number. 2. Change the ending of the parent alkane from -e to -ol and use a number to show the location of the -OH group; for cyclic alcohols, the carbon bearing the -OH group is carbon-1. 3. Name and number substituents and list them in alphabetical order.
Nomenclature • In the IUPAC system, a compound containing two hydroxyl groups is named as a diol, one containing three hydroxyl groups as a triol, and so forth. • IUPAC names for diols, triols, and so on retain the final "-e" in the name of the parent alkane. • We commonly refer to compounds containing two hydroxyl groups on adjacent carbons as glycols.
Physical Properties Alcohols are polar molecules. • The C-O and O-H bonds are both polar covalent.
Physical Properties In the liquid state, alcohols associate by hydrogen bonding.
boiling points (°C) CH3OH65°CH3CH2CH2OH 97° CH3CH3 -88°CH3CH2CH2CH3 0° CH3Cl -24° CH3CH2CH2Cl 46° PhOH182°CH3CH2CH2CH2OH118° PhCH3110°(CH3)2CHCH2OH108° PhCl132° (CH3)3COH 83°
solubility (g / 100 mL H2O) ∞ ∞ 8.3 2.4 0.6 0.05 7.8 10.0 ∞ 3.6 CH3CH2OH CH3CH2CH2OH CH3CH2CH2CH2OH CH3CH2CH2CH2CH2OH CH3CH2CH2CH2CH2CH2OH CH3CH2CH2CH2CH2CH2CH2CH2OH CH3CH2OCH2CH3 (CH3)2CHCH2OH (CH3)3COH C6H11OH
Preparing Alcohols Fermentation zymase ethanol sucrose Alkene Hydration H H H H H H H H
Oxidation of Alcohols (1°) (2°)
Common Nomenclature IUPAC Nomenclature • dialkyl "ether" • dialkyl "ether" • "alkoxy"
pentane bp 36°C (diethyl) ether bp 36°C 7.8 g/100 mL 1-butanol bp 118°C 8.3 g/100 mL
Naming thiols Alkane + thiol 1-propanethiol 2-propene-1-thiol
CH3CH2OH(bp 78°C)CH3OCH3 (bp -24°C) CH3CH2SH (bp 35°C)CH3SCH3(bp 37°C)
Oxidation sulfide (thioether) sulfoxide sulfone
-helix -helix
-helix -helix
-helix -helix
-helix -helix -pleated sheet
-pleated sheet -helix -helix -pleated sheet
-pleated sheet -helix salt bridge -helix -pleated sheet
-pleated sheet -helix salt bridge -helix hydrogen bond -pleated sheet
-pleated sheet -helix hydrogen bond salt bridge -helix hydrogen bond -pleated sheet
hydrophilic interaction to water -pleated sheet -helix hydrogen bond salt bridge -helix hydrogen bond -pleated sheet
hydrophilic interaction to water -pleated sheet -helix hydrogen bond hydrophobic interaction salt bridge -helix hydrogen bond -pleated sheet
hydrophilic interaction to water -pleated sheet -helix hydrogen bond hydrophobic interaction salt bridge -helix hydrogen bond -pleated sheet
hydrophilic interaction to water -pleated sheet -helix hydrogen bond hydrophobic interaction salt bridge disulfide bond -helix hydrogen bond -pleated sheet