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1、Chapter 4Alcohols and Alkyl HalidesThis chapter introduces chemical reactions and their mechanisms by focusing on two reactionsthat yield alkyl halides.(1)alcohol + hydrogen halideROH +HX RX+H2O(2)alkane + halogenX2 RH+RX+HXBoth are substitution reactionsOverview of Chapter4.1IUPAC Nomenclature of A

2、lkyl HalidesThere are several kinds of IUPAC nomenclature.The two that are most widely used are: functional class nomenclature substitutive nomenclatureBoth types can be applied to alcohols and alkyl halides.IUPAC NomenclatureName the alkyl group and the halogen asseparate words (alkyl + halide)CH3F

3、CH3CH2CH2CH2CH2ClCH3CH2CHCH2CH2CH3HIBrFunctional Class Nomenclature of Alkyl HalidesName the alkyl group and the halogen asseparate words (alkyl + halide)CH3FMethyl fluorideCH3CH2CH2CH2CH2ClPentyl chlorideCH3CH2CHCH2CH2CH3HIBr1-Ethylhexyl bromideCyclohexyl iodideFunctional Class Nomenclature of Alky

4、l HalidesName as halo-substituted alkanes.Number the longest chain containing the halogen in the direction that gives the lowest number to the substituted carbon.CH3CHCH2CH2CH3CH3CH2CH2CH2CH2FBrCH3CH2CHCH2CH3ISubstitutive Nomenclature of Alkyl HalidesName as halo-substituted alkanes.Number the longe

5、st chain containing the halogen in the direction that gives the lowest number to the substituted carbon.CH3CHCH2CH2CH3CH3CH2CH2CH2CH2F1-FluoropentaneBr2-BromopentaneCH3CH2CHCH2CH3I3-IodopentaneSubstitutive Nomenclature of Alkyl HalidesClHalogen and alkyl groups are of equal rank whenit comes to numb

6、ering the chain.Number the chain in the direction that gives the lowest number to the group (halogen or alkyl) that appears first.CH3CH3ClSubstitutive Nomenclature of Alkyl HalidesCl5-Chloro-2-methylheptaneCH3CH32-Chloro-5-methylheptaneClSubstitutive Nomenclature of Alkyl Halides4.2IUPAC Nomenclatur

7、e of AlcoholsName the alkyl group and add alcohol as aseparate word.CH3CH2OHCH3CH3CCH2CH2CH3OHCH3CHCH2CH2CH2CH3OHFunctional Class Nomenclature of AlcoholsName the alkyl group and add alcohol as aseparate word.CH3CH2OHEthyl alcoholCH3CH3CCH2CH2CH3OH1,1-Dimethylbutyl alcoholCH3CHCH2CH2CH2CH3OH1-Methyl

8、pentyl alcoholFunctional Class Nomenclature of AlcoholsName as alkanols. name by -ol.Replace -e ending of alkaneNumber chain in direction that gives lowest number to the carbon that bears the OH group.CH3CH2OHCH3CH3CCH2CH2CH3OHCH3CHCH2CH2CH2CH3OHSubstitutive Nomenclature of AlcoholsName as alkanols.

9、 name by -ol.Replace -e ending of alkaneNumber chain in direction that gives lowest number to the carbon that bears the OH group.CH3CH2OHEthanolCH3CH3CCH2CH2CH3OH2-Methyl-2-pentanolCH3CHCH2CH2CH2CH3OH2-HexanolSubstitutive Nomenclature of AlcoholsOHHydroxyl groups outrank alkyl groups whenit comes to

10、 numbering the chain.Number the chain in the direction that gives the lowest number to the carbon that bears the OH groupCH3CH3OHSubstitutive Nomenclature of AlcoholsOH6-Methyl-3-heptanolCH3CH35-Methyl-2-heptanolOHSubstitutive Nomenclature of Alcohols4.3Classes of Alcohols and Alkyl HalidesAlcohols and alkyl halides are classified as primarysecondary tertiaryaccording to their degree of substitution.Degree of substitution is determined by counting the number of carbon atoms directly attached tothe carbon that bears the halogen or h