Table 7: Effect of solvent on the catalytic activity of benzyl alcohol oxidation by Cr(II) complexes at optimum conditions.
Catalyst | Solventa | Yield (%) | Conversion (%) | Selectivity (%) | |||
BAb | BZc | Side products | R | ||||
CrLA1 | CH2Cl2 | 53 | 3 | 31 | 13 | 87 | 61 |
Acetone | 67 | 6 | 18 | 9 | 91 | 74 | CHCl3 | 25 | 3 | 84 | 24 | 76 | 33 | DMF | — | — | 100 | — | 100 | 0 |
CrLA2 | CH2Cl2 | 40 | 2 | 39 | 19 | 81 | 49 |
Acetone | 57 | 5 | 23 | 16 | 84 | 68 | CHCl3 | 24 | 1 | 55 | 20 | 80 | 30 | DMF | — | — | 96 | 4 | 96 | 0 |
CrLA3 | CH2Cl2 | 36 | 2 | 31 | 31 | 69 | 50 |
Acetone | 51 | 4 | 17 | 28 | 72 | 71 | CHCl3 | 15 | 3 | 48 | 34 | 66 | 23 | DMF | — | — | 89 | 11 | 89 | 0 |
aThe oxidation of benzyl alcohol (R) (1.0 mmol) catalyzed by complex CrLA2 (0.02 mmol) with aqueous H2O2 (3.00 mL) in 10 mL acetonitrile for 1–6 h. bThe yield based on GC results, selectivity percentage of the target oxide product BA and the other product BZ. cThe other side products are mainly of BZ. |