1.3.4 Sarrett’s Oxidation
The Sarrett’s reagent is a mixture of CrO3 and pyridine. This reagent also oxidizes the primary and secondary alcohols to aldehydes and ketones (Scheme 5). The acid sensitive groups and other oxidizable groups remain unaffected but the only problem is the removal of excess pyridine after the reaction.
F. Freeman, Encylopedia of Reagents for Organic Synthesis, John Wiley and Sons, Inc., L. A. Paquette, Ed., New York, 1995, 5, 2272. |
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Scheme 5 |
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Scheme 6 |
1.3.5 Collins-Ratcliff Oxidation
A 1:2 mixture of CrO3 and pyridine in dichloromethane (DCM) is known as Collins reagent or Collin-Ratcliff reagent. It also oxidizes the primary alcohols and secondary alcohols to aldehydes and ketones, respectively (Scheme 6). This reaction works under mild reaction condition without affecting other functional groups and the only disadvantage is the excess use of the reagent.