ORGANIC CHEMISTRY Chapter 6 Physical Properties o Solubil o Very low solubilities in water o Relatively nonpolar solvents ° Toxicity o Many chloroalkanes have a cumulative toxicity and are carcinogenIc o Boiling points o chCL CH Br. chchcl cha=chcl cha=chBr are gas o In general, higher alkyl halides(Xcl, Br, Iare all quids Department of Chemistry, Xiamen University
ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 6 Physical Properties Solubility Very low solubilities in water. Relatively nonpolar solvents. Toxicity Many chloroalkanes have a cumulative toxicity and are carcinogenic. Boiling points CH3Cl, CH3Br, CH3CH2Cl, CH2=CHCl, CH2=CHBr are gas. In general, higher alkyl halides(X=Cl,Br,I) are all liquids
ORGANIC CHEMISTRY Chapter 6 6.3 Nucleophilic Substitution Reactions 亲核取代反应 Department of Chemistry, Xiamen University
ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 6 6.3 Nucleophilic Substitution Reactions 亲核取代反应
ORGANIC CHEMISTRY Chapter 6 N R-X R-Nu+Ⅹ Nucleophile Alkyl halide Product Halide ion (substrate) Heterolysis Leaving group Nucleophilic substitution reaction HO:+ CH2-Cl- CH2-OH Cl CH20:+ CH, CHo-Br CHr CHo-oCH2 Br I:+CH3 CH, CH, -CI CH CHCHo-I CI Department of Chemistry, Xiamen University
ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 6 Nu + R X R Nu + X Nucleophile Alkyl halide Product Halide ion (substrate) Heterolysis Leaving group Nucleophilic substitution reaction HO + CH3 Cl CH3 OH + Cl CH3O + CH3CH2 Br CH3CH2 OCH3 + Br CH3CH2CH2 Cl CH3CH2CH2 + I + Cl I
ORGANIC CHEMISTRY Chapter 6 Questions When does the carbon-halogen bond break? Does it break at the same time that the new bond between the nucleophile and the carbon forms? Nu: +R-X Nu--R--X R-Nu+X g Or does carbon-halogen bond break first? R-X—R++X And then Nu:+R+—-R-Nu Department of Chemistry, Xiamen University
ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 6 Questions When does the carbon-halogen bond break? Does it break at the same time that the new bond between the nucleophile and the carbon forms? Nu + R X Nu R X R Nu + X δ δ Or does carbon-halogen bond break first? R X R + X And then Nu + R R Nu