Treatment of a mixture of cyclohexanol and ferrous perchlorate with hydrogen peroxide in acetonitrile led to a mixture of cyclohexanediols and cyclohexanone. In acetohitrile containing perchloric acid, cis-1,3-cyclohexanediol accounted for 71.9% of the diol produced. Under these conditions, hydrogen removal at C-3 occurred stereoselectively cis to the hydroxyl group. A mechanism for this aliphatic hydroxylation which involves an initial directed hydrogen abstraction (kH/kD = 1.18), free radical oxidation by Fe3+, and stereoselective carbonium ion capture was proposed. Evidence for the stepwise nature of this process was derived from analysis of the Fe2+/H2O2 oxidation of 7-hydroxynorbornane (6). Hydrogen abstraction from 6 was found to occur stereoselectively syn to the hydroxyl group and subsequent 2,6-hydride transfers result in a 1:1 ratio of syn.exo and anti,exo diols (8 and 9).
All Science Journal Classification (ASJC) codes
- Colloid and Surface Chemistry