Methods of preparation of alkyl halides

The chapter groups the methods of making alkyl (and aryl) halides into five families, developed one at a time in sections 10.3.1-10.3.5: making an alkyl halide starting from the corresponding alcohol by replacing its -OH group (three different reagent choices are compared: a halogen acid HX, a phosphorus halide PX3/PCl5, or thionyl chloride SOCl2); making an alkyl halide starting from a hydrocarbon, either by addition of a hydrogen halide across an alkene's double bond or by direct halogenation of an alkene to a vicinal dihalide; converting one alkyl halide into another by a halogen-exchange reaction (Finkelstein for iodides, Swartz for fluorides); making an aryl halide by electrophilic aromatic substitution of a halogen onto a benzene ring; and making an aryl halide by Sandmeyer's reaction, which replaces the nitrogen of a diazonium salt with a halogen. Read together, these five routes co …