Conversion of alcohol into a Leaving Group Form Tosylate (p-TsCl,pyridine) Use strong acid (H3O+) Convert to Alkyl Halide(HX,SOC12,PBr3)
Conversion of Alcohol into a Leaving Group • Form Tosylate (p-TsCl, pyridine) • Use strong acid (H3O+ ) • Convert to Alkyl Halide (HX, SOCl2 , PBr3 )
Formation of p-Toluenesulfonate Esters R一O号H+HO子S CH,R-0-S《 CH3 +H2O alcohol TsOH alkyl tosylate,ROTs p-toluenesulfonic acid a p-toluenesulfonate ester
Formation of p-Toluenesulfonate Esters
Substitution and Elimination Reactions Using Tosylates OH TsCI Nuc: (substitution) +-0Ts pyridine or elimination: (elimination) C-C+B-H + B:
Substitution and Elimination Reactions Using Tosylates
Summary of Tosylate Reactions R一OTS OH R-OH OTs hydroxide alcohol R-OTs + C=N R一C=N OTs cyanide nitrile R一OTs + Br R—Br + OTs halide alkyl halide R-OTs R-O R-O—R' OTs alkoxide ether R-OTs + :NH3 R一NH-OTs ammonia amine salt R一OTs LiAIH4 R一H OTs LAH alkane
Summary of Tosylate Reactions
Best to use p-TsCl with pyridine CH3 CH; p-tolue nesulfonyl chloride pyridine reacts with HCl as it forms No co H
Best to use p-TsCl with pyridine OH CH3 C CH3 lS O O p-toluenesulfonyl chloride OS O O CH3 CH3 N H C l pyridine reacts with HCl as it forms N +