Mechanism Na2Cr207+H20+2H2S04 2 H2CrO4 2 NaHSO4 OCrO3H HO- + H2O 2°alcohol Chromic Acid(CrV④ Chromate ester 6H2 ke tone (Cr IV)
Mechanism OH + C r O O HO OH OCrO3H Chromate ester + H2O N a2 C r2O7 + H2O + 2 H2 SO4 2 H2CrO4 + 2 NaHSO4 Chromic Acid (Cr VI) H O CrO3H O H2 O + H3O + HCrO3 2 alcohol o ketone (Cr IV)
Oxidation of 1 Alcohols CH,OH 一OH NaCr207 H2SO4 cyclohexyl methanol cyclohexanecarboxylic acid (92%)
Oxidation of 1o Alcohols
PCC oxidizes 1 Alcohols to Aldehydes cro.c H PCC pyridinium chlorochromate
PCC oxidizes 1o Alcohols to Aldehydes N H CrO3 C l pyridinium chlorochromate PCC
Pyridinium Chlorochromate (PCC) ·PCC is a complex of chromium trioxide, Pyridinium chlorochromate (PCC): pyridine,and HCI. ·Oxidizes primary N+H CrO,CI- alcohols to aldehydes. CrO3'pyridine·HCI Oxidizes secondary or pyH+CrO,CI- alcohols to ketones
Pyridinium Chlorochromate (PCC) • PCC is a complex of chromium trioxide, pyridine, and HCl. • Oxidizes primary alcohols to aldehydes. • Oxidizes secondary alcohols to ketones
Oxidation of 1 Alcohols to Aldehydes:PCC OH CrO3'pyridine-HCl(PCC) R-C-H R-C-H CH2Cl2 H primary alcohol aldehyde pyH+CrO3CI-(PCC) CH,(CH2)5一CH2OH CH2Cl2 CH3(CH2)s-C-H 1-heptanol heptanal (78%)
Oxidation of 1o Alcohols to Aldehydes: PCC