Table 1.
Method comparison for oxidation of cholestryl acetate (1) by tert-butyl hydroperoxide.
| catalyst/ additive (mol%) |
Oxidant | TBHP (equiv) |
Solvent | Time (h) |
temp. (°C) |
Yield 2, (%) |
|---|---|---|---|---|---|---|
| NaClO2 (116 %) |
T-HYDRO | 10 | MeCN | 80 | 60 | 66 ref. (5) |
| CrO3 (5 %)/NMI |
T-HYDRO | 7 | PhCF3 | 23 | 40 | 74 ref. (6) |
| Mn3(OAc)9 (10 %) |
t-BuOOH/ decane |
5 | EtOAc | 48 | 40 | 85 ref. (7) |
| BiCl3 (5 %) |
t-BuOOH/ decane |
10 | MeCN | 22 | 70 | 82 ref. (8) |
| CuI (3 %)/ Bu4NBr (6 %) |
T-HYDRO | 7 | benzene | 24 | 70 | 63 ref. (9) |
| Co(OAc)2 (2.2 %) |
t-BuOOH/ decane |
6 | benzene | 48 | 70 | 70 (ref. 10) |
| RuCl3 (0.7 %) |
T-HYDRO | 10 | Cyclohex ane |
24 | 20 | 75 (ref. 12) |
| Rh2(cap)4 (1.0 %) |
T-HYDRO | 5 | (CH2Cl)2 | 20 | 40 | 80 |
| Rh2(cap)4 (0.1 %) |
T-HYDRO | 8 | (CH2Cl)2 | 20 | 40 | 77 |