Basic Chemistry Copyright © 2011 Pearson Education, Inc. 1 Chapter 17 Organic Chemistry 17.1 Alkanes Compounds in food contain many organic compounds.

Basic Chemistry Copyright © 2011 Pearson Education, Inc. 2 IUPAC Names

Basic Chemistry Copyright © 2011 Pearson Education, Inc. 3 Structural Formulas Alkanes are written with structural formulas that are expanded to show each bond condensed to show each carbon atom and the attached hydrogen atoms

Basic Chemistry Copyright © 2011 Pearson Education, Inc. Drawing Structural Formulas Carbon atoms in a chain maintain their tetrahedral shape are connected in a zigzag pattern are drawn as two dimensional can be written in many ways 4

Basic Chemistry Copyright © 2011 Pearson Education, Inc. Some Structural Formulas 5 Rotation of the end CH 3 -groups provides different representations for butane.

Basic Chemistry Copyright © 2011 Pearson Education, Inc. 6 Learning Check Draw the condensed structural formula for heptane.

Basic Chemistry Copyright © 2011 Pearson Education, Inc. 7 Solution Heptane, an alkane, has seven carbon atoms in its carbon chain. CH 3 ─CH 2 ─CH 2 ─CH 2 ─CH 2 ─CH 2 ─CH 3

Basic Chemistry Copyright © 2011 Pearson Education, Inc. 8 Learning Check Name each of the following: A. CH 3 ─CH 2 ─CH 2 ─CH 3 B. CH 3 ─CH 2 ─CH 2 ─CH 2 ─CH 2 ─CH 2 ─CH 2 ─CH 3

Basic Chemistry Copyright © 2011 Pearson Education, Inc. 9 Solution A. CH 3 ─CH 2 ─CH 2 ─CH 3 four carbon atoms; butane B. CH 3 ─CH 2 ─CH 2 ─CH 2 ─CH 2 ─CH 2 ─CH 2 ─CH 3 eight carbon atoms; octane

Basic Chemistry Copyright © 2011 Pearson Education, Inc. 10 Isomers of Butane Isomers have the same molecular formula have different atomic arrangements for butane are a straight chain and a branched chain

Basic Chemistry Copyright © 2011 Pearson Education, Inc. 11 Naming Alkanes with Substituents In the IUPAC system, a carbon branch is named as an alkyl group halogen atoms are named as halo

Basic Chemistry Copyright © 2011 Pearson Education, Inc. 12 Naming Alkanes

Basic Chemistry Copyright © 2011 Pearson Education, Inc. 13 Example of Naming an Alkane Give the IUPAC name of CH 3 CH 3  CH 3 ─CH─CH─CH 2 ─CH 2 ─CH 3 STEP 1 Write the alkane name of the longest continuous chain of carbon atoms. hexane STEP 2 Number the carbon atoms starting from the end nearer a substituent. CH 3 CH 3   CH 3 ─CH─CH─CH 2 ─CH 2 ─CH

Basic Chemistry Copyright © 2011 Pearson Education, Inc. 14 Example of Naming an Alkane (continued) STEP 3 Give the location and name of each substituent as a prefix to the alkane name. CH 3 CH 3 methyl groups on carbons 2 and 3  CH 3 ─CH─CH─CH 2 ─CH 2 ─CH ,3-dimethylhexane

Basic Chemistry Copyright © 2011 Pearson Education, Inc. 15 Learning Check Give the IUPAC name of Cl CH 3  CH 3 ─CH 2 ─CH─CH─CH 3

Basic Chemistry Copyright © 2011 Pearson Education, Inc. 16 Solution STEP 1 Write the alkane name of the longest continuous chain of carbon atoms. pentane STEP 2 Number the carbon atoms starting from the end nearer a substituent. Cl CH 3  CH 3 ─CH 2 ─CH─CH─CH

Basic Chemistry Copyright © 2011 Pearson Education, Inc. 17 Solution (continued) STEP 3 Give the location and name of each substituent as a prefix to the alkane name. Cl CH 3   CH 3 ─CH 2 ─CH─CH─CH chloro-2-methylpentane chloro on carbon 3methyl on carbon 2

Basic Chemistry Copyright © 2011 Pearson Education, Inc. 18 Learning Check Give the IUPAC name for the following: Cl CH 3 | | CH 3 ─CH 2 ─CH─CH 2 ─C─CH 2 ─CH 3 | Cl

Basic Chemistry Copyright © 2011 Pearson Education, Inc. 19 Solution STEP 1 Write the alkane name of the longest continuous chain of carbon atoms. heptane STEP 2 Number the carbon atoms starting from the end nearer a substituent. Cl CH 3 | | CH 3 ─CH 2 ─CH─CH 2 ─C─CH 2 ─CH | 6 7 Cl

Basic Chemistry Copyright © 2011 Pearson Education, Inc. 20 Solution (continued) STEP 3 Give the location and name of each substituent as a prefix to the alkane name. Cl CH 3 | | CH 3 ─CH 2 ─CH─CH 2 ─C─CH 2 ─CH | 6 7 Cl 3,5-dichloro-5-methylheptane chloro on carbon 3 methyl and chloro on carbon 5

Basic Chemistry Copyright © 2011 Pearson Education, Inc. Drawing Alkane Formulas 21

Basic Chemistry Copyright © 2011 Pearson Education, Inc. 22 Learning Check Draw the condensed structural formula for 2-bromo-4-chlorobutane.

Basic Chemistry Copyright © 2011 Pearson Education, Inc. 23 Solution STEP 1 Draw the main chain of carbon atoms. For butane, there are four carbon atoms in the chain. C─C─C─C STEP 2 Number the chain and place the substituents on the carbons indicated by the numbers. Br  C─C─C─C─Cl

Basic Chemistry Copyright © 2011 Pearson Education, Inc. 24 Solution (continued) Br  C ─ C ─ C ─ C ─ Cl STEP 3 Add the correct number of hydrogen atoms to give four bonds to each C atom. Br  CH 3 ─CH─CH 2 ─CH 2 ─Cl Needs 3 H Needs 1 H Need 2 H each