1. 1 12.5 Cycloalkanes Chapter 12 Alkanes

2. 2 Cycloalkanes: Are rings of carbons that can be drawn as geometric figures. Have a general formula of C n H 2n or 2 H less than the alkane. propane C 3 H 8 cyclopropane C 3 H 6. butane C 4 H 10 cyclobutane C 4 H 8. Are named with the prefix cyclo- in front of the corresponding alkane name. Cycloalkanes

3. 3 Formulas of Cycloalkanes

4. 4 A cycloalkane with: One substitutuent is named by placing the name of the substituent in front of the cycloalkane name. Two or more substitutuents is named by numbering the ring in the direction that gives the lower numbers to the substituents. Naming Cycloalkanes

5. 5 Cycloalkanes with Side Groups

6. 6 Constitutional Isomers The rigid ring in a cyclic structure prevents rotation of substitutuents bonded to the ring. A cyclic structure with two substituents has two isomers called cis-trans isomers. The cis isomer, has two substituents on the same side of the ring. The trans isomer, has two substituents on opposite sides of the ring.

7. 7 Cis-Trans Isomers The compound 1,2-dichlorocyclopropane has cis-trans isomers. Cl atoms on same side opposite sides