Jones oxidation of 1-o-tolyl-propan-2-ol; 1-o-tolyl-propan-2-oneSyntheticPage 171 (2001)
(
http://www.syntheticpages.org/browse.php?&action=1&page=4&id=171)
Chemicals UsedChromium trioxide (Lancaster) 1-o-tolyl-propan-2-ol Acetone (GPR) conc H
2SO
4 (BDH) water
ProcedureChromium trioxide (12.8 g, 0.128 mol) was dissolved in 18 mL water (142 mL/molCrO
3)in a beaker. The resulting solution was cooled to 0°C whereupon 11 mL conc H
2SO
4 (87 mL/mol CrO
3) was added dropwise. The solution was diluted with 36 mL water (285 mL/mol Cr0
3) and cooled to 0°C. A solution of the alcohol (19.2 g, 0.128 mol) in acetone (80 mL) (600mL/mol CrO
3) was cooled to 0°C and the Jones reagent added slowly, maintaining a temperature <20°C.
Stirring was continued for 3 h at 0°C. Sodium bisulfite was added in small portions until the brown colour of the chromic acid had disappeared from the upper layer. The top layer was decanted and the lower layer extracted with ether (2 x 200 mL). The extracts were combined and washed with NaCl solution, dried over MgSO
4, filtered and concentrated in vacuo. The resulting brown oil was purified by chromatography on silica gel with petrol:ethyl acetate (10:1) as the eluent yielding the title compound as a yellow oil (14.2g, 75%).
Author's CommentsAlthough this reaction is very commonly used in synthesis, I found it difficult to find exact conditions when searching. The literature assumes that everyone knows how to make the reagent! Although I have only carried out this reaction once, I found it high yielding and easy to follow.