Organic Chemistry,6th Edition 林司 L.G.Wade,Jr. Chapter 14 I 15 ALcohols Key Notes Hydrogen bonding;Acidity;Lucas reagent; Dehydration;Williamson synthesis By Junru Wang Email:wangjr07@163.com 西北农林科技大学理学院
西北农林科技大学理学院 By Junru Wang Email: wangjr07@163.com Chapter 14 & 15 Alcohols Organic Chemistry, 6th Edition L. G. Wade, Jr. Key Notes Hydrogen bonding; Acidity; Lucas reagent ; Dehydration ; Williamson synthesis
CONTENTS Structure Properties of Alcohols Preparation of alcohols Functional group transformation ■C-C bond formation Reduction of Carbonyl Reactions of Alcohols Acid-base reactions Elimination:Dehydration to alkene ■ Synthesis of alkyl halides:Substitution to form alkyl halide Oxidation to aldehyde,ketone ■Reduction to alkane -Synthesis of mesylate and tosylates ■Esterification Williamson synthesis of ether
CONTENTS ❖Structure & Properties of Alcohols ❖Preparation of alcohols ◼ Functional group transformation ◼ C-C bond formation ◼ Reduction of Carbonyl ❖Reactions of Alcohols ◼ Acid-base reactions ◼ Elimination:Dehydration to alkene ◼ Synthesis of alkyl halides: Substitution to form alkyl halide ◼ Oxidation to aldehyde, ketone ◼ Reduction to alkane ◼ Synthesis of mesylate and tosylates ◼ Esterification ◼ Williamson synthesis of ether
Sec 1 Structure Properties of Alcohols 0.96A 0.96A 104.50 H 108.9° water water water methyl alcohol methyl alcohol methyl alcohol Copyright2010 Pearson Prentice Hall,Inc. Hydroxyl (-OH)functional group Oxygen is sp3 hybridized. The H-O-H angle in water is 104.5 The C-O-H angle in methyl alcohol is 108.9. 1、-C,O;Sp hybridized;O:不等性SP杂化 2、一O-H,C-0为极性共价键 3、-OH,-I;R-,+I
Sec 1 Structure & Properties of Alcohols ❖Hydroxyl (-OH) functional group ❖Oxygen is sp3 hybridized. ❖The H—O—H angle in water is 104.5° . ❖The C—O—H angle in methyl alcohol is 108.9° . 1、－C，O； SP3 hybridized; O:不等性SP3杂化 2、－O-H，C-O为极性共价键 3、－OH, -I; R-, +I
Physical Properties H Alcohols are polar compounds.They interact with themselves and with other polar compounds by dipole- dipole interactions. Dipole-dipole interaction:the attraction between the positive end of one dipole and the negative end of another. -Unusually high boiling points due to hydrogen bonding between molecules. -Small alcohols are miscible in water,but solubility decreases as the size of the alkyl group increases. 00a H H 0 1u=1.69D 0=1.30D u=0.08D CH,CH, HC CH H.C CH ethanol,MW 46 dimethyl ether,MW 46 propane,MW 44 bp78℃ bp-25C bp-42C
Physical Properties - + + O H H H C H ❖Alcohols are polar compounds. They interact with themselves and with other polar compounds by dipoledipole interactions. ❖Dipole-dipole interaction: the attraction between the positive end of one dipole and the negative end of another. ◼Unusually high boiling points due to hydrogen bonding between molecules. ◼Small alcohols are miscible in water, but solubility decreases as the size of the alkyl group increases
Physical Properties Hydrogen bonding:when the positive end of one dipole is an H bonded to F,O,or N (atoms of high electronegativity)and the other end is F,O, or N the strength of hydrogen bonding in water is approximately 21 kJ (5 kcal)/mol hydrogen bonds are considerably weaker than covalent bonds -nonetheless,they can have a significant effect on physical properties Alcohol ether Hydrogen bond H R hydrogen bond donor acceptor
Physical Properties ❖Hydrogen bonding: when the positive end of one dipole is an H bonded to F, O, or N (atoms of high electronegativity) and the other end is F, O, or N ◼the strength of hydrogen bonding in water is approximately 21 kJ (5 kcal)/mol ◼hydrogen bonds are considerably weaker than covalent bonds ◼nonetheless, they can have a significant effect on physical properties R O H H O O R R R O H H O R R O H H O R