25 g Cr(VI)O 3 is dissolved in 25 mL H 2SO 4 (conc.). Solution is added very slowly to 75 mL H 2O that had been cooled to 0 oC and is stirring.
Contributed by Professor Al Hagedorn:
This recipe for Jones reagent should work well for simple cases, but likely has a bit too much acid for really delicate ones. The ratio of "H+" to CrO 3 should be 3:1, as required by the stoichiometry for alcohol to ketone oxidation. I like 2.67 Molar CrO 3 in 3.00 Molar H 2SO 4 (i.e., 8.00 Normal). It doesn't need analytical chemistry precision, but I've had good results with a reasonably good titration of the H 2SO 4, and drying the CrO 3 in advance. Titrating the substrate with this sauce, I've been able to oxidize secondary alcohols without hurting tertiary pseudoaxial alcohols benzylic to activated aromatic rings; it doesn't take much excess acid to mess those up…