Platinum nanoparticles supported on zirconia mediated synthesis of N-acyl and N-(tert-butoxycarbonyl)amines from nitroarenes and azides

A convenient and useful protocol has been designed for the synthesis of N-aryl acetamides from the corresponding nitro compounds via a reductive N-acylation process using bi-functional, recyclable heterogeneous platinum nanoparticles supported on zirconia [Pt(0)/ZrO2] catalyst, employing molecular hydrogen as the environmentally benign reductant and the corresponding anhydrides as acylating agents. N-Boc protected amines were also synthesized in similar lines, from the corresponding azides. The reaction is successfully performed under mild conditions to afford good to excellent yields of the products. The solid bifunctional-catalyst, Pt(0)/ZrO2 is quantitatively recovered by simple centrifugation and reused for multiple cycles with consistent activity and selectivity.

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► One-pot synthesis of carbamates from corresponding nitro and azide compounds.
► Environment friendly methodology, utilizing molecular hydrogen as the reductant.
► Bi-functional Pt(0)/ZrO2 shows high efficiency in reduction followed by protection.
► Catalyst reused several times without loss of activity.
► Industrially viable reaction smoothly affording good yields under mild conditions.