Efficient hydration of nitriles promoted by simple amorphous manganese oxide using reduced amounts of water

Hydration of various kinds of nitriles could efficiently be promoted by amorphous MnO2 using reduced amounts of water (2 equiv or less), giving the corresponding primary amides in moderate to high yields. The observed catalysis was truly heterogeneous, and the retrieved MnO2 could be reused without an appreciable loss of its high catalytic performance.