Alcohols .. organic analog of water Hydrogen bond donor O-Hd+ Od- Hydrogen bond acceptor - 42oC boiling point propane ethanol + 78 oC

Alcohols Solubility in H2O (g/100 mL) formula boiling point H3C O H O C2H5OH 78 miscible C4H9OH 117 7.9 CH3OH 65 miscible C6H13OH 158 0.5 C8H17OH 194 insoluble H3C O H d+ d- O H d+ d- CH2CH2CH3 CH2 CH2CH2CH2H2C H3C O H H3C O H d+ d-

Alcohols - Nomenclature 1. Longest continuous chain with - OH 2. Root name + “-ol” 3. Position of - OH given smallest number 4. Ring of cyclic alcohols numbered from - OH 5. Compounds with more than one - OH called “diols” or “triols”

Alcohols 4-ethyl- 3- heptan ol 6-methyl- 2,4- octane diol phenol 6 4 2 7 1 5 3 2 4 5 3 1 6-methyl- 2,4- octane diol 6 7 8 phenol

classes of alcohols 1o alcohol 1- butanol 2o alcohol 2- propanol 4 3 2 1 1- butanol 2o alcohol 2- propanol 3o alcohol 2-methyl- 2- propanol

Alcohols Classify and name: 1o 2o 3o 1-methyl cyclohexanol 1o 2-phenyl- 1-propanol

Alcohols - reactions dehydration reverse of hydration of alkenes a) electrophile b) nucleophile step 1 C H O : C H OH H+ : : H+

C H O : step 2 C H O H : + step 3 C H + H+ regenerate catalyst

hydration - dehydration + H2O [alcohol] Q = K = 5 [alkene] [H2O] G = -RT ln K/Q

2-butanol major minor major product = most substituted H C CH3 H H3C H 4 1 2 3 2-butanol H 4 3 C CH3 H 1 H3C H 1 2 H 2 3 C C H H 4 CH3 H 1-butene trans- 2-butene major minor major product = most substituted

What are dehydration products of 1-methylcyclohexanol? a) major product b) minor product CH3 H H major product

Oxidation of alcohols Primary alcohols: carboxylic acid 1o alcohol 1+ 2- 2- 2- 1+ 1- 3+ 1+ 1+ 1+ 1+ 2- carboxylic acid 1o alcohol aldehyde [O] = oxidizing agent dichromate Cr2O72- Cr3+ permanganate MnO4- oxidation = loss of e- density from C 1. binding O 2. removing H

Oxidation of alcohols Secondary alcohols: 2o alcohol ketone no reaction 2o alcohol ketone

Oxidation of alcohols Tertiary alcohols: no reaction