Week # 3 Lecture # 7 and 8 - Alcohols, Phenols, and ThiolsConcepts: Classes of alcohols - (primary, secondary, tertiary), hydrogen bonding, polarity of all functional groups, solubility.Reaction Summary:4. Hydration: Alkene + water -7. Dehydration : Alcohol +heat 8. Oxidation - pri. Alcohol: Pri. Alcohol + (O) 9. Oxidation - sec. Alcohol: Sec. Alcohol + (O) 10. Oxidation - aldehyde: Aldehyde + (O) 11. Ether Synthesis: Alcohol + alcohol Types or Classes of Alcohols:The alcohols may be classified according to the number of carbonsattached to the carbon with the -OH group. Ques. 1: Write the IUPAC name of the alcohols above.Primary alcohol: The -OH carbon has only one other carbon attached.Example (A) above. Secondary alcohol: The -OH carbon has two other carbons attached.Example (B) above.Tertiary alcohol: The -OH carbon has three other carbons attached.Example (D) aboveQues. 2: What type of alcohol is (C) above? Ques. 3: Classify the following alcohols and give the IUPAC names:H2CCH2H2CCH3HOCH3CHCH2H3COHCH2CHCH3HOCH3CH3CH3COHCH3ABCDPolarity of Organic Compounds:http://www.elmhurst.edu/~chm/vchembook/213organicfcgp.htmlThe greater the electronegativity difference between atoms in a bond, the more polar thebond. Partial negative charges are found on the most electronegative atoms, the others are partially positive. In general, the presence of an oxygen is more polar than a nitrogenbecause oxygen is more electronegative than nitrogen.The combination of carbons and hydrogens as in hydrocarbons or in the hydrocarbon portion of a molecule with a functional group is always NON-POLAR.Polarity and Boiling Point:The polarity of the molecules determines the forces of attraction between the molecules in the liquid state. Polar molecules are attracted by the opposite charge effect (the positive end of one molecule is attracted to the negative end of another molecule. Molecules have different degrees of polarity as determined by the functional group present.Principle: The greater the forces of attraction, the higher the boiling point; or the greater the polarity, the higher the boiling point.Ques. 4: Polarity of Functional Groups (relatively constant number of C, H's)Func gp salt amide acids Aldehydeketoneamine ester etheralkaneFormula C4H7O2-M+C3H7NO C3H6O2C3H6O C4H11N C4H8O2C3H18O C4H10StructureNameRank1 2 3 4 5 6 7 8CH3CH2CCH3HOH3CH3CCHCHCH3OHH3CCH3CCHCH3OHH3CH3CCH2H2CCH3HOCH3CHCH3HOABCDEAn abbreviated polarity list to know well is: Amide > Acid > Alcohol > Amine > Ether > AlkaneHYDROGEN BONDINGIntroduction: The hydrogen bond is really a special case of dipole forces. A hydrogen bond is theattractive force between the hydrogen attached to an electronegative atom of one molecule and anelectronegative atom of a different molecule. Usually the electronegative atom is oxygen, nitrogen, or fluorine, which has a partial negative charge. The hydrogen then has the partial positive charge. To recognize the possibility of hydrogen bonding, examine the Lewis structure of the molecule. The electronegative atom must have one or more unshared electron pairs as in the case of oxygen and nitrogen, and has a negative partial charge. The hydrogen, which has a partial positive chargetries to find another atom of oxygen or nitrogen with excess electrons to share and is attracted to the partial negative charge. This forms the basis for the hydrogen bond.Hydrogen Bond Definition: The hydrogen on one molecule attached to O or N that is attracted to an O or N of a different molecule.In the graphic on the left, the hydrogen is partially positive and attracted to the partially negative charge on the oxygen. Because oxygen has two lone pairs, two different hydrogen bonds can be made to each oxygen. This is a very specific bond as indicated. Some combinations which are nothydrogen bonds include: hydrogen to another hydrogen or hydrogen to a carbon.Ques. 5: Draw an example of three water molecules engaged in hydrogen bonding.Ques. 6: Write the structure of methanol and then draw three molecules of methanol engaged in hydrogen bonding.Ques. 7: Draw the figure for hydrogen bonding between two or three ethanol molecules.Ques. 8: An ether molecule is also a derivative of a water molecule. Both hydrogens have been replaced by carbons. a) Write the structure for dimethyl ether and diethyl ether. b) Is hydrogen bonding between ether molecules possible?Solubility - "Likes dissolve Likes" - Application of PolaritySolubility is a measure of the ability of two substances to dissolve in each other. The relative solubility of one compound in another depends largely on the type and strengthof intermolecular bonds between the molecules in the pure compounds. If the bonding strength between molecules of substance A is roughly equal to the intermolecular forcesof substance B, substances A and B will probably be soluble in each other. For example, methyl alcohol dissolves in water because the hydrogen bonds between water molecules and those between alcohol molecules are of roughly equal strength. The hydrogen bonds between similar molecules can be broken and replaced by hydrogen bonds between alcohol and water molecules. Alcohol molecules can "slip" into the network of hydrogen bonds in water. Both molecules have polar O-H bonds. The attraction of opposite partial charges allows the mixing of water and alcohol molecules - such compounds are said to be hydrophilic-"water loving.Ques. 9: Draw several water and methanol molecules hydrogen bonded togetherOn the other hand, hydrocarbons and water are not soluble in each other. Hydrocarbon alkanes do not have any hydrogen bonds nor any polar attractions. Thus the only appreciable attractions are between water molecules, so they effectively "squeeze out" the hydrocarbon molecules. At the same time the hydrocarbon moleculestend to prefer "their own company" and effectively keep out water molecules. These CH3CH2CCH3HOH3CH3CCHCHCH3OHH3CCH3CCHCH3OHH3CH3CCH2H2CCH3HOCH3CHCH3HOABCDEcompounds are said to be hydrophobic-"water hating". Hydrocarbons have non-polar carbon-carbon and carbon-hydrogen bonds. The behavior of alkane or hydrocarbon parts in all molecules imparts a non-polar character to the molecule. Solubility principle:The above relationships are usually summed up by the common generalization: "Likes dissolve Likes". This means that a polar solvent will dissolve polar compounds but will not dissolve non-polar compounds.The