11. 4 Oxidation of alcohols Primary alcohols can be oxidized to aldehydes and carboxylic acids R—cH2OH—R—cHO一 R—cooH 10 Alcohol Aldehyde Carboxylic acid CH, CHCH,OH K2 Cr2O7 CH3CH2CH2CHO 1-Butanol H2SO4 Butanal bp,117.7°C bp,75.7C50% Cu CH3CH,OH CH3CH2OH H2 300°C Dehydrogenation
11.4 Oxidation of alcohols Primary alcohols can be oxidized to aldehydes and carboxylic acids. R CH2 OH [ O ] R CHO R COOH 1 o Alcohol Aldehyde Carboxylic acid [ O ] CH3CH2CH2CH2OH 1-Butanol K2Cr2O7 H2 SO4 CH3CH2CH2CHO Butanal bp, 117.7 o C bp, 75.7 o C 50% CH3CH2OH Cu 300 o C CH3CH2OH + H2 Dehydrogenation
PCC CH3CH2CH2CH2OH a CH3 CH, CH,CHO Butanol CH2Cl225°C Butanal PCC— Pyridinium chlorochromate吡啶三氧化铬 Cro2 +hcl+ H Pyridine o=Cr-=o CI Pyridinium chlorochromate 吡啶三氧化铬
CH3 CH2 CH2 CH2 OH 1-Butanol CH3 CH2 CH2 CHO Butanal PCC 25 o CH2 Cl 2 C CrO3 + HCl + N N O Cr O O Cl - H + Pyridinium chlorochromate 吡 啶 三 氧 化 铬 Pyridine PCC Pyridinium chlorochromate 吡 啶 三 氧 化 铬
11. 4B Oxidation of 1 alcohols to carboxylic acids, Oxidation of 2 alcohols to ketone KMnO4, KOH HCl CH3CH,CH2CH2OH CH3CH2CHCOOK CH3 CH2CH,COOH 1-Butanol CH3CH2 CHCH3 KMnO, KOH- CH3 CH, CCH3 OH 2-Butanol Butanone OH HCro Acetone 35 Cyclooctane Cyclooctanone 环癸醇 环癸酮
11.4B Oxidation of 1o Alcohols to carboxylic acids, Oxidation of 2o alcohols to ketone. CH3CH2CH2CH2OH 1-Butanol CH3CH2CH2COOK KMnO4 , KOH HCl CH3CH2CH2COOH CH3 CH2 CHCH3 OH 2-Butanol KMnO4 , KOH CH3CH2CCH3 O Butanone OH Cyclooctanol H2CrO4 Acetone 35 oC O Cyclooctanone 环 癸 醇 环 癸 酮
11.4D Mechanism of chromate oxidations(铬酸氧化机理) R H HO—cr-0H R cr—oH t H,o R H Step 2 Chromate ester(铬酸酯) R R 0—cr-oH 4+ 0 t hcrO3 Ho R R Cr 6+ Ketone C 4+ Chromate ester(铬酸酯)
11.4D Mechanism of Chromate oxidations （铬酸氧化机理） Step 1 R C R O H H + HO Cr O O OH R C R O H Cr O O OH + H2O Chromate ester (铬 酸 酯 ） R C R O H Cr O O OH R R O + HCrO3 - + H3O + Step 2 Ketone Cr 6+ Cr 4+ 6+ 4+ H2O Chromate ester (铬 酸 酯 ）