sodium dichromate; sulfuric acid in diethyl ether 0.25 h; Ambient temperature;

1: 99 percent / Br2 / diethyl ether / 0.25 h 2: 1.) KOH, 2.) BF3*MeOH / 1.) 95percent aq. EtOH, sonication, 30 min, r.t., 2.) MeOH, reflux, 10 min 3: 95 percent / aq. Hg(OAc)2 / tetrahydrofuran / 0.33 h / Ambient temperature 4: 85 percent / aq. Na2Cr2O7, H2SO4 / diethyl ether / 0.25 h / Ambient temperature View Scheme

1: 95 percent / aq. Hg(OAc)2 / tetrahydrofuran / 0.33 h / Ambient temperature 2: 85 percent / aq. Na2Cr2O7, H2SO4 / diethyl ether / 0.25 h / Ambient temperature View Scheme

1: 1.) KOH, 2.) BF3*MeOH / 1.) 95percent aq. EtOH, sonication, 30 min, r.t., 2.) MeOH, reflux, 10 min 2: 95 percent / aq. Hg(OAc)2 / tetrahydrofuran / 0.33 h / Ambient temperature 3: 85 percent / aq. Na2Cr2O7, H2SO4 / diethyl ether / 0.25 h / Ambient temperature View Scheme

5-(2-hydroxyethyl)-4-methyl-3-(phenylmethyl)thiazolium chloride; triethylamine in 1,4-dioxane

1: m-chloroperbenzoic acid 2: 1) NaI, nPrI, 2) H2SO4 / 1) DMSO, 2) MeOH View Scheme

sulfuric acid; 1-iodo-propane; sodium iodide 1) DMSO, 2) MeOH; Multistep reaction. Title compound not separated from byproducts;