Nomenclature According to IUPAC,alkyl halides are treated as alkanes with a halogen substituent. The halogen prefixes are Fluoro-,Chloro-,Bromo-and lodo-. Examples: F-CH2CH3 H 、CHs ci H fluoroethane trans-1-chloro-3-methylcyclopentane Often compounds of CH2X2 type are called methylene halides.(CH2Cl2 is methylene chloride). CHX,type compounds are called haloforms.(CHI,is iodoform). CX type compounds are called carbon tetrahalides.(CF is carbon tetrafluoride). Alkyl halides can be primary (1),secondary(2)or tertiary (3). H R R-X R- -X R- H H R 10 20 Other types: A geminal(gem)dihalide has two halogens on the same carbon. A vicinal dihalide has halogens on adjacent carbon atoms. BrBr CI CI RR R-R RR gem-dibromide vicinal dichloride Ch06 Alkyl Halides (landscape) Page 3Ch06 Alkyl Halides (landscape) Page 3 Nomenclature According to IUPAC, alkyl halides are treated as alkanes with a halogen substituent. The halogen prefixes are Fluoro-, Chloro-, Bromo- and Iodo-. Examples: Often compounds of CH2X2 type are called methylene halides. (CH2Cl2 is methylene chloride). CHX3 type compounds are called haloforms. (CHI3 is iodoform). CX4 type compounds are called carbon tetrahalides. (CF4 is carbon tetrafluoride). Alkyl halides can be primary (1°), secondary (2°) or tertiary (3°). Other types: A geminal (gem) dihalide has two halogens on the same carbon. A vicinal dihalide has halogens on adjacent carbon atoms. F CH2CH3 Cl H H CH3 fluoroethane trans-1-chloro-3-methylcyclopentane R H H X 1 o R R H X 2 o R R R X 3 o R Br Br R gem-dibromide R R Cl R Cl R vicinal dichloride