Organic Chemistry Chapter 12 Oxygen and Sulfur in

Organic Chemistry Chapter 12 Oxygen and Sulfur in Organic Compounds 1

Part 01 The Alcohols 2

Alcohols • Organic molecules that contain the hydroxyl functional group, OH • General formula for an alcohol is ROH 3

- can be viewed as derivatives of water, where one hydrogen is replaced by an alkyl or aryl group H O H R O H Ar O H (Aryl group – benzene derivative such as phenyl group) 4

Classification of Alcohols • Primary alcohol, 1º • Secondary alcohol, 2º • Tertiary alcohol, 3º 5

Classification of Alcohols • Primary alcohol, 1º - has one R group and 2 Hs on the carbinol carbon - C to which the –OH is bonded 6

H H H C OH H H Ethanol 7

• Secondary alcohol, 2 o - has two R groups and 1 H on the carbinol carbon H H C C H H OH H 2 -propanol 8

• Tertiary alcohol, 3 o - has three R groups and 0 H on the carbinol carbon H CH 3 H H C C H H OH H 2 -methyl-2 -propanol 9

Nomenclature of alcohols • • All names end in -ol Determine parent chain (longest continuous chain that contains the – OH group) The alcohol group has priority in numbering the chain If more than 1 hydroxyl group, use di or tri before the ol • diols or triols • diols are known as glycols • Keep the entire parent chain name; don’t chop 10 off any letters. (i. e. pentanediol)

Nomenclature of alcohols • • Number the chain to give the carbon(s) containing the –OH group the lowest possible number(s). • Place this number in front of the name of the alcohol, separated by a hyphen. Follow rules to label substituents just like you would with any other organic compound. • Lowest possible numbers and alphabetical order; use di, tri etc. if more than one of the same substituent 11

Examples: Name the following alcohols and classify as 1 o, 2 o or 3 o. H H H C C OH H H 1 -butanol, 1 o 12

H H H C C H H H OHH 2 -butanol, 2 o 13

H H H C C C H H OH H 2 -pentanol, o 2 14

H H OH H C C C H H H OH 1, 1 -pentanediol, 1 o 15

H H OH H NH 2 H C C C H H H 1 -amino-3 -pentanol, 2 o 16

OH cyclopentanol, o 2 17

OH Cl cis-2 -chloro-1 -cyclopentanol, 2 o 18

OH OH cis-1, 2 -cyclohexanediol, o 2 19

OH phenol, o 2 20

OH OH catechol, o 2 21

OH CH 3 o 2 cresol, 2 -methylphenol 22

CH 2 OH benzyl alcohol, o 1 23