Here, we report a chromium-catalyzed activation of acyl C-O bonds with magnesium for amidation of esters with nitroarenes. Low-cost chromium(III) chloride shows high reactivity in promoting amidation by using magnesium as reductant and chlorotrimethylsilane as additive. It provides a step-economic strategy to the synthesis of centrally important amide motifs using inexpensive and air-stable nitroarenes as amino sources.