Chapter Organic Chemistry Haloalkanes, Alkenes, and Alkynes Functional Groups Haloalkanes Timberlake LecturePLUS 1999

Timberlake LecturePLUS 1999 Functional Groups Part of an organic molecule where chemical reactions take place Composed of an atom or group of atoms Replace a H in the corresponding alkane Provide a way to classify organic compounds Timberlake LecturePLUS 1999

Some Types of Functional Groups Haloalkane -F, -Cl, -Br CH3Cl Alcohol -OH CH3OH Ether -O- CH3-O-CH3 Aldehyde Ketone Timberlake LecturePLUS 1999

More Functional Groups Carboxylic acid -COOH CH3COOH Ester -COO- CH3COOCH3 Amine -NH2 CH3NH2 Amide -CONH2 CH3CONH2 Timberlake LecturePLUS 1999

Timberlake LecturePLUS 1999 Haloalkanes An alkane in which one or more H atoms is replaced with a halogen (F, Cl, Br, or I) CH3Br 1-bromomethane Br (methyl bromide) CH3CH2CHCH3 2-bromobutane Cl chlorocyclobutane Timberlake LecturePLUS 1999

Timberlake LecturePLUS 1999 Learning Check HA1 Name the following: Timberlake LecturePLUS 1999

Timberlake LecturePLUS 1999 Solution HA1 Name the following: bromocyclopentane 1,3-dichlorocyclohexane Timberlake LecturePLUS 1999

Timberlake LecturePLUS 1999 Substituents List other attached atoms or group in alphabetical order Br = bromo, Cl = chloro Cl Br CH3CHCH2CHCH2CH2CH3 4-bromo-2-chloroheptane Timberlake LecturePLUS 1999

Timberlake LecturePLUS 1999 Learning Check HA2 The name of this compound is: Cl CH3 CH3CH2CHCH2CHCH3 1) 2,4-dimethylhexane 2) 3-chloro-5-methylhexane 3) 4-chloro-2-methylhexane Timberlake LecturePLUS 1999

Timberlake LecturePLUS 1999 Solution HA2 The name of this compound is: Cl CH3 CH3CH2CHCH2CHCH3 3) 4-chloro-2-methylhexane Timberlake LecturePLUS 1999

Haloalkanes as Anesthetics Halothane (Fluothane) F Cl F C C Br F H Fluothane is a haloalkane that is widely used as an anesthetic, which is a compound that decreases the ability of the nerve cells to conduct pain. Timberlake LecturePLUS 1999

Timberlake LecturePLUS 1999 Ozone Layer Ozone layer Stratosphere (10-30 miles Above Earth) Timberlake LecturePLUS 1999

Chlorofuorocarbons (CFCs and the Ozone Layer ozone O3 layer absorbs most of the sun’s harmful radiation. CFCs - chlorofluorocarbons - are depleting that ozone layer. CFCs are used as Freons in refrigeration, air conditioning, and foam insulation. Their use in spray cans is no longer allowed. Timberlake LecturePLUS 1999

Chlorofuorocarbons and the Ozone Layer In the stratosphere, the CFCs react with the high-energy UV radiation from the sun UV light CF2Cl2 CF2Cl + Cl Freon-12 free radical Timberlake LecturePLUS 1999

Chlorofuorocarbons and the Ozone Layer To become stable, the Cl acquires an electron from ozone O3 and produces ClO. Cl + O3 ClO + O2 The presence of ClO in the atmosphere is an indicator of the disappearance of ozone. Timberlake LecturePLUS 1999

Impact of Loss of Ozone Layer According to the National Academy of Sciences, each 1% loss of ozone increases by 2% the amount of UV radiation reaching the earth. More UV radiation means more skin cancer and cataracts in humans, more intense photochemical smog, and lower crop yields. Timberlake LecturePLUS 1999